Category Archives: maps

Mapping Racism And Assessing the Success of the Digital Humanities

This week, The Chronicle of Higher Education published a piece (now behind a paywall) written by Prof. Timothy Brennan. In it, the digital humanities as a field is essentially assessed as a “bust.” A concluding critique seemed particularly harsh: “Rather than a revolution, the digital humanities is a wedge separating the humanities from its reason to exist — namely, to think against prevailing norms.” Although I and many others who engage with DH have a number of qualms with this assessment, I decided that one way to rebut it was simply by exploring one sub-field largely excluded from the article: GIS and digital mapping.

What is below is a transcription of my Forbes column for this week, which looks at how digital mapping has changed our understanding and access to issues regarding race, segregation, and social justice in the United States. I think that Prof. Brennan might wish to see just a few of the DH projects that challenge “prevailing norms.”


How are mapping projects changing the way that we understand our history of racism, segregation and prejudice in America? A number of digital projects are now using GIS (geographic information systems) in order to geolocate social justice movements, visualize both historical and present racism and highlight racial issues, all using the familiar interface of the map.


An interactive map of Washington D.C. in 1860 shows the segregation of people of color within the city through a new project called ‘Placing Segregation.’

In order to explore the impact of spatial humanities on social justice issues, I spoke to GIS specialist Dr. Rob Shepard, creator of the new ‘Placing Segregation’ project, which combines the geolocation of hundreds of written records with historical maps in order to visualize segregation in mid-19th century American cities such as Washington, D.C., Omaha and Nashville.

People of color have been using maps to visualize racism for a long time. As Shepard notes, “W.E.B. Du Bois famously geolocated and documented basic socioeconomic information about individual households in The Philadelphia Negro, as part of a sociological study in the 1890s. Consequently, the granular GIS-style approach I’ve been using in mapping residents for Placing Segregation – and my work with the project Civil War Washington before it – is not completely unique or special to digital humanities. And I don’t claim that.”


Map by W.E.B. Du Bois of Philadelphia’s Seventh Ward drawn in 1899.

Many prominent African-American activists at the time turned to maps and other data visualizations in order to help the public–and even the president–to understand the detrimental effects of slavery on the country. In 1900, W.E.B. Du Bois, Booker T. Washington and a lawyer by the name of Thomas J. Calloway began to develop visualizations for display at the Paris World Fair.

As Allison Meier noted in an article on these visualizations, “Du Bois’s charts (recently shared by data artist Josh Begley on Twitter) focus on Georgia, tracing the routes of the slave trade to the Southern state, the value of black-owned property between 1875 and 1889, comparing occupations practiced by blacks and whites, and calculating the number of black students in different school courses (2 in business, 2,252 in industrial).” Data visualizations, now a key part of digital humanities approaches to organizing and visualizing archived records, have in fact long been a (analog) tool used to illustrate the suffering of African-Americans in the U.S.


W.E.B. Du Bois created a map called: “The Georgia Negro: Land owned by Negroes in Georgia, U.S.A. 1870-1900” for the 1900 Paris Exposition.

In the past decade, as the movement towards digital approaches to history have gained steam both within universities across the country and in journalism, historians addressing race have again returned to the earlier methods established by African-Americans following the Civil War.

Shepard remarks on just a few of these projects and their ability to teach students using free resources online; a movement to democratize information called open access: “These resources are freely available to classrooms and students who have so much to gain from accessible information. University of Richmond’s Visualizing Emancipation project for instance, not only provides its research GIS data for download and use, but also the team has developed accompanying lesson plan documentation and the site encourages higher education instructors to get in touch with the team for more specialized assignments using the geographic datasets.”

It says a lot when a university within the former capital of the confederacy begins to invest heavily in visualizing and teaching the American history of inequality. Such projects often depend on federal funding agencies like the National Endowment for the Humanities.


The University of Richmond’s Visualizing Emancipation project maps slavery’s end during the American Civil War. The project is partially funded by the National Endowment for the Humanities.

Today there are dozens of digital projects focused on the African-American experience. Recently, The Colored Conventions Project housed at the University of Delaware brought together an epic list of over a hundred such projects. The list of digital initiatives include Mapping the Stacks, which visualizes Chicago’s black community archives from the 1930s to the 1970s. As I have previously noted, the Equal Justice Initiative has also launched the Lynching in America project, which provides access to interactive maps, archival documents and oral histories of lynching in the U.S.

The impact of these projects goes far beyond visualization; they champion a novel approach to informing the public. Pier Gabrielle Foreman, a professor of English and Black American Studies & History at the University of Delaware and the founding director of the Colored Conventions Project notes the import of such digital work in terms of information and preservation: “In the West, so many of the documents that record Black history have been devalued and discarded. Now they exist in remnants, a single letter instead of a full set of correspondences in in one collection, a single newspaper instead of a full run in another library. Digital Humanities projects allow researchers to better piece together this scattered archive. In the case of the, we have been able to help reassemble the records of six decades of nineteenth-century Black political organizing–for voting and legal rights, for educational access, justice and jobs.” Digital Humanities can be used as a form of high-tech quilting that likewise stitches together disparate parts of the past.

Digital mapping and database construction can allow us to reconstruct, preserve, and visualize vestiges of the past, but academics engaged in this work are often dependent on the public for aid. As Foreman notes, “Without the distributed, collaborative and collective work of volunteer transcribers, national teaching partners, librarians and student leaders, this work would not be possible. Though this is collective work, we have a better sense of  how long Black people have been organizing for civil rights—and how consistently those rights have been denied.”

Additionally, digital mapping initiatives can react to crisis in real time. Recent map-a-thons at Columbia University, MIT and at Princeton’s digital humanities center, for instance, have brought together academics and the public to use open-source mapping to aid the hurricane relief efforts in Puerto Rico.


Interactive map of the Lynching in America project from the Equal Justice Initiative.

Projects like Placing Segregation, Lynching in America, The Colored Conventions Project and myriad other digital humanities projects exemplify that there is a great deal of in-depth assessment and interrogation happening within digital projects that goes well beyond amusing data aggregation. From W.E.B. Du Bois to today, the use of geographic visualization has frequently been grounded in allowing the public access to crucial information. In the process, these maps and the humans behind them have taught us about the devastating impact of racism.




Were Pagan Temples All Smashed Or Just Converted Into Christian Churches?

This week over at the Forbes column [access it here], I discuss an article in the new volume of the Journal of Late Antiquity (10.1) It is a great piece of scholarship written by ancient historian Feyo L. Schuddeboom and is called “The Conversion of Temples in Rome.” The article effectively uses archaeological evidence for temple conversion within the city of Rome during the period of Late Antiquity (ca.300-800 CE in this case) in order to further dismantle the myth that all Roman temples were smashed to bits by angry pagans. Using the case study of Rome, Schuddeboom also suggests that temples being converted to churches was usually a pragmatic act rather than one meant to demonstrate the “triumph” of Christianity over paganism.

The article has a helpful map within it. It was also a great excuse to insert some pictures from Santa Maria Antiqua; a 6th century church in the Roman Forum. I was lucky enough to be able to see this converted quadriporticus church near to the ramp that leads up to the Palatine from the Forum Romanum and to glimpse at its recently restored frescoes (see images below).

Enjoy these photos and this amazing new issue of the JLA. If you care to read about another converted temple in Rome, feel free to read my article on the history of Roman Curiae. The Curia Senatus was a Roman temple and also the Roman Senate House–since senate meetings could only technically be held within a consecrated space in the city of Rome.

Digital Palmyra: Resources for Researching the Ancient City

Yesterday on the Forbes blog, I discussed recent attempts to reconstruct the ancient busts of Palmyra damaged by ISIS and repatriate them back to Syria. As I suggested in the post, such efforts highlight the import of digital methodologies such as 3D printing and photogrammetry, but also underscore art as an umbilical cord that allows us to create an emotional connection. Much like Delphi, art is often an ὀμφαλός (Greek for ‘navel’).

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Limestone relief of a woman and two children from Pamyra, dated to c.150 CE. Now at the Harvard Art Museums in Cambridge, MA. The inscription at the top reads: ‘Ba’altega, daughter of Hairan. Alas! Sim’on here son; Hairan, her son.’  (1908.3)

Palmyrene funerary busts in particular are an evocative medium that forces the viewer to make direct eye contact with the Syrians of antiquity. When I was at the Vatican Museums recently, I was amazed to see both children and their parents actually pausing on their way to the Sistine Chapel in order to gaze at the Vatican’s small collection of Palmyrene busts (a selection of which are below).

Here are a few projects and resources for investigating ancient Palmyra (and a few other sites) online, although this is by no means a comprehensive list.

Memory Matrix (MIT): An aesthetic project using digital technologies to recreate lost structures from the Middle East. As they note: “The Memory Matrix is a monument that explores the possibilities for future heritage creation, employing new fabrication techniques and transcultural workshops. The Matrix is made of border fences carrying over 20,000 small fluorescent Plexiglas elements. These elements are laser cut with holes outlining vanished heritage from Syria, Iraq, Yemen and beyond.” This video is amazing.

Memory Matrix at MIT from Azra Aksamija on Vimeo.

The Legacy of Ancient Palmyra (Getty Research Institute): As per usual, the Getty Research Institute has used its massive digital archives and powers of good curation for good. Check out the Palmyra site map, the large collection of travel photos, and the resources for research on Palmyra. In the “modern” section, there is a helpful (if rather upsetting) explanation for why those portrait busts became collected by museums in Europe and the U.S. following the expansion of travel tourism in the 19th century: “As tourist photographs of the site began to circulate more widely, so did Palmyra’s artifacts, especially the famous funerary portrait busts (some of which are featured in this exhibition). Today, one can see thousands of Palmyrene antiquities outside the region: in American, Western European, Russian, and Turkish museums that had been secured during the late Ottoman rule (1876–1922) and subsequently during the French Mandate (1923–46).

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Temple of Bel, cella entrance , Jean-Baptiste Réville and Pierre Gabriel Berthault after Louis-François Cassas. Etching. Platemark: 18 x 11.4 in. (46 x 29 cm). From Picturesque travels of Syria, Phenicia, Palestine, and Lower Egypt (Paris, ca. 1799), vol. 1, pl. 46. ​​Image via The Getty Research Institute’s ‘The Legacy of Ancient Palmyra.’ 

Monuments of Syria (Dr. Ross Burns): A list of the historical sites in Syria. There is an area of the website just for Palmyra. There are lots of historical images and primary sources that can easily be put into a syllabus for educators. It also explores the destruction of monuments that has thus far occurred during the Syrian Civil War and the encroachment by ISIS.

On the Polychromy of Ancient Palmyra” (Alex Nagel, Smithsonian Institution): A post on the polychromy added to Palmyrene portrait busts. The Smithsonian has indeed been engaging in analysis of the polychrome remnants left on at least one bust in their collection. As Nagel remarks about a particular limestone relief with remnants of red on the jewelry: “Microscope images would make painted details much more visible and a red colorant on the statue has recently been identified by scientific analysis. Qualitative elemental analysis of a small sample taken shows the presence of Al, Si, Ca and Fe with a strong presence of iron.”

On a side note: You can often see the red left on inscriptions from antiquity. Red paint was applied to make them stand out to readers; a common use of color for textual emphasis. In the middle ages, manuscript assistants called rubricators added red to certain letters to make them stand out. There is even a famous monk known for his ability to apply red, who was given the nickname Rubricius.

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Funerary relief bust; Syria, 231 CE; Limestone; Freer Gallery of Art; F1908.236 (Freer Gallery).

Sketchfab and Palmyra: As I pointed out in the Forbes article, there are a number of 3D models popping up online which are either made on-site from a museum bust or from a composite of photos that produce photogrammetric data that can be used to create a 3D model. As I have written about before, there are indeed ethics that must be applied to 3D printing cultural heritage and there is indeed the danger of “digital colonialism”–particularly if the object is not contextualized or you are making a profit from its display. Right now my favorite model is a 2nd-3rd c. bust from the Louvre.


These are just a few of the interesting digital projects focused on Palmyra right now. My hope is that the creation of both digital and museum-based relationships to the Syrian past will not only make us reflect on current cultural heritage issues, but also serve to create a connection to the present. Syria’s civil war continues to take the lives of thousands of civilians and the death toll now stands at close to 500,000. Consequently, these digital projects are fantastic, but we must keep in mind that accepting the art of Syria but rejecting its people is not an option. 


A Palmyrene bust of a woman with polychrome jewelry now at the Musée de Grenoble (Photo taken by David Meadows and used with permission).

To The Black Sea And Back: The Late Antique Dura-Europos ‘Shield’ Map


Dura-Europos as visualized on the Pelagios Project’s Peripleo map.

Dura-Europos is an ancient site on the Euphrates river in modern-day Syria. The objects excavated at the site by Yale University (later famously led by Mikhail Rostovtzeff), and the French Academy of Inscriptions and Letters during the 1920s and 1930s provide some of the most vivid wall paintings, mosaics, and material culture from the ancient world that we have today. One of the most stunning finds is a parchment shield cover that dates to around 260 CE, which has a map of the Black Sea on it. There is debate over whether it was on the inside of a shield used by a soldier or was a dedicatory object; however, the map provides a rare glimpse into how geography was visualized.


Surviving parchment fragment of the Black Sea ‘Shield Map’ from Dura Europos dated to before 260 CE. It depicts staging posts along the Black Sea (Bibliotheque Nationale Gr. Suppl. 1354, no. 5). Images via Cumont (see citation below) with added scale and color enhancement. 

Hand drawing of the map via Wikimedia (D. Herdemerten Hannibal21, CC BY-SA 3.0).

The parchment contains a number of place names in Greek, but is interestingly mixed with the distances in Roman miles. Here is the transcription as provided by

[Π]αν[υσὸς ποτ(αμὸς) μί(λια)   ̣  ̣]
Ὀδεσ[σὸς μί(λια)   ̣  ̣]
Βυβόνα [μί(λια)   ̣  ̣]
Κάλ[λ]ατις μί(λια)   ̣  ̣
5Τομέα μί(λια) λγ
Ἴ[σ]τρος ποτ(αμὸς) μί(λια) μ
Δάνουβις ποτ(αμὸς) [μί(λια)   ̣  ̣]
Τύρα μί(λια) πδ
Βορ[υ]σ[θέν]ης [μί(λια)   ̣  ̣]
10Χερ[σ]όν[ησος -ca.?- ]
Τραπε[ζοῦς -ca.?- ]
Ἀρτα[ξάτα μί(λια)   ̣  ̣]

The map is oriented west-southwest and thus is a reminder that most maps did not consistently orient north until the early modern period. The stations on the shield maps are listed in Greek with vivid white, while the ships are manned by small sailors. It is a two-dimensional visualization of a Euxine route that shows the mix of languages and peoples in the late antique Eastern Mediterranean. In particular, it visualizes the Roman relationship with places in modern Armenia. An interesting mention of Ἀρτα[ξάτα] (Artaxata=Artashat) hints at the Roman connection to this busy commercial center. 

Although the map was likely on a round shield, the only surviving scutum from antiquity is from Dura-Europos. It too dates to the 3rd c. CE. It is now at the Yale Art Gallery. Image is in the Public Domain.

As historian Dragoş Hălmagi puts it, “The surviving sequence runs clockwise along the shores of Black Sea, from Odessos in Thrace to the Cimmerian Bosporus, and indicates a symmetric original design, consisting of a circular coast surrounding the Black Sea and perhaps parts of the Mediterranean, as well.” About a century earlier, the historian and governor Arrian had written a work in the form of a letter to the emperor Hadrian (131/2 CE) called Περίπλους τοῦ Εὐξείνου Πόντου (The Periplus of the Euxine Sea) while in Cappadocia. Arrian demonstrates the beginnings of the late antique fascination with the geography of this area that would continue into the third and fourth centuries CE when the rise of the Sassanids would be a point of major contention.   

The circumnavigation of the Black Sea as recounted by Arrian, Periplus Maris Euxini, in a firsthand report (1–11) and a secondhand description (12–25). Adapted by Erenow from A. Liddle, ed. and trans., Arrian, Periplus Ponti Euxini (London: Bristol Classical Press, 2003), 136–39, maps 1–2.

As we know from the Antonine Itinerary and many other itinerary inscriptions, the listing of locations and the miles between was quite common for itineraria, but this is our earliest surviving example of a route map from antiquity. Today this rather small piece of parchment lives in Paris, in the Bibliothèque nationale de France (ms. Suppl. gr. 1354 V, nr. 5), but seeing as I had never viewed a color version of it before, I thought it might be nice to get a glimpse at that technicolor world of the Romans I am always talking so much about. 

Attempted restoration of the entirety of the shield as drawn in Figure 1 in Arnaud (1989).


Monsieur Pascal Arnaud, ‘Une deuxième lecture du “bouclier” de Doura-Europos,’ Comptes rendus des séances de l’Académie des Inscriptions et Belles-Lettres, 133e année, N. 2, (1989): 373- 389.

Franz Cumont, ‘Fragment de bouclier portant une liste d’étapes,’ Année 6.1 (1925 ): 1-15. 

Leif Isaksen, “The application of network analysis to ancient transport geography: A case study of Roman Baetica,” Digital Medievalist. 4. DOI:

Dragoş Hălmagi, “Notes on the Dura Europos map,”  CICSA Journal, New Series 1 (2015): 41-51.


The Itinerarium Egeriae: Mapping Egeria’s Pilgrimage On Candlemas

In the Roman Catholic Church, the celebration held forty days after Christmas is the festival of Candlemas (February 2). Candlemas recognizes the presentation of Jesus in the temple and the purification of the Virgin Mary forty days after giving birth (Luke 2:22-29). This was in accordance with Jewish purity law (Lev. 12:4) which required women who had just given birth to remain separate from the temple. On this Candlemas, I wanted to take a look back at the development of the liturgical calendar in Late Antiquity and also to consider the role of late antique women in shaping our knowledge of both liturgical practice and the geography of piety in the early Christian Mediterranean.

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An illustration of the presentation of Jesus in the temple from the Menologion of Basil II (ca. 1000 CE). I have indeed used a screenshot from the digitized version of Vat.Gr.1613 that can be accessed in its entirety at the Digital Vatican Library website.

We know that the emperor Justinian set Candlemas within the city of Constantinople and elsewhere in the East for February 2. In the year 542 CE, the emperor decreed this celebration as a means of entreating the purity of the Virgin Mary to remedy the outbreak of plague that was ravaging the city at that time. However, the origins of the festival likely lay in the early fourth century. Around the year 381-384, a pilgrim text written by a woman named Egeria, who derived either from southern France or northwestern Spain, remarked on the festival in Jerusalem thusly: 

‘Sane quadragesimae de epiphania ualde cum summo honore hic celebrantur. ‘

Her reference to a celebration held on the fortieth day after Epiphany likely demonstrates that Candlemas was originally celebrated on February 14, exactly forty days from Epiphany celebrated on January 6. Notably, when celebrated on February 14, Candlemas was then just the day before the popular Roman Lupercalia of February 15–where the raucous but traditional Roman religious purificatory rites of februa were carried out. Christian or not, the month of February was then a time for purification in the fourth and fifth centuries.


Triumphal arch mosaic in the Basilica of Santa Maria Maggiore (Rome). This is the oldest known artistic depiction of the presentation of Jesus at the temple. (Image via Wikimedia under a CC-BY-SA-3.0 License and first noted to me by Caitlin Green).

As it happens, my medieval Latin class is currently discussing the import of ritual, liturgy, and the early Christian calendar by translating a portion of Egeria’s writings. Although she uses some quirky Latin, she provides a pivotal example of female prose writing in Late Antiquity. Notably, the only surviving manuscript is the so-called Codex Arretinus, an 11th century fragmentary text only found in the Italian city of Arezzo in the late 19th century. We know little about whether she was a nun (she does often address her fellow dominae) or just a learned pilgrim, but we can say that she wrote the Itinerarium Egeriae (or Peregrinatio Aetheriae) in an epistolary format that reflected on her travails while on pilgrimage to sites such as Mount Sinai and Jerusalem. She also pivotally records her liturgical experience while attending services in the Church of the Holy Sepulcher in Jerusalem.

The geography detailed in Egeria’s extraordinary itinerary letters help us to reconstruct the broader network of movement amongst pilgrims in the late antique Mediterranean. Her itinerary, along with earlier itineraries such as the Itinerarium Burdigalense (Bordeaux Itinerary) of ca.333, together give us a good idea of the pilgrimage routes regularly used in the fourth century by both men and women. With the advent of GIS, there has been a push to map these pilgrimage routes, which in their original formats formed a textual list rather than a geospatial visualization. As one student noted: “A medieval Trip Advisor.” The best modern geographic visualization of these itineraries for you to use in your classes is at the Pelagios project’s Recogito site. Here you can find a number of late antique texts that can be “read” geo-spatially.


Map of the Bordeaux Itinerary as visualized by Recogito via the Pelagios Project.

Although we can map the routes listed in the anonymous Bordeaux Itinerary rather more easily and confidently, Egeria presents more of a challenge to modern geographers. Certainly the order of the sites that she mentions–Mount Sinai, Jerusalem, Constantinople–can give us some idea of the likely routes and roads she may have taken, especially when compared to other texts (e.g., Epiphanius) and set alongside the existing Roman road networks. But it is still admittedly oftentimes speculative. That is why I am always hesitant to point students to maps like the one at the ‘Egeria Project,’ which makes her text seem much more complete than it actually is.


Screenshot from, which has an incredible number of downloadable maps and itineraries that range from antique pilgrim routes to the modern day. This is the downloadable excel sheet for the sites from the Bordeaux Itinerary [Access Here].

I will be discussing the issue of “imaginary” or uncertain geography more at the Clerical Exile conference in April, but the very mapping of these routes can serve as an argument to suggest that we know more than we really do; a danger within the study of Late Antiquity that I and my colleague Candida Moss have similarly remarked upon. As ancient historian Ryan Horne recently asserted, uncertainty must be represented and flagged on maps, even if it is not a very satisfying practice. But, really, maps are not here to provide us complete satisfaction. Think of the use of dotted lines or blinking place-markers as a possible geographic signpost for inserting all those textual “maybes” and “perhaps-s” that frequently pepper academic writing in order to show that we are unsure. It is also a reminder that translating texts to different languages may cause problems, but so too does its translation to a different visual medium (text -> map).

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Recogito’s Map of the sites mentioned in Egeria’s Itinerary (381-384 CE). Map tiles created by the AWMC and used under a CC-BY-NC-3.0 license.

This was a quick post to point out some resources for studying a quite worthy late antique lady and using her to help reconstruct the world of late antique pilgrimage. I often read books on cartography in the late antique world that focus solely on the myriad men that came to shape the early Christian worldview. However, it must be remembered that even if writers like Egeria didn’t give us a diagrammatic representation of an area, many women contributed to the broader geographic discourse in the later empire. Collectively, these texts inform how we visualize a world we are no longer a part of, but which we frequently attempt to access. I think Prof. Moss put it best when she said: “Christian social networks, patterns of pilgrimage and missionary activity, and the art of letter writing united Christian communities and networks across the empire…Physical geography is webbed with social networks navigated by correspondence, plotted by travel, and reimagined by ancient cartographers” (2012: 21). Our vision of the late antique Mediterranean is still a complex, imperfect, and often deceptive network of people and places rather than a straightforward map, but then again, so is the world of today.

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Egeria’s mentions of Jerusalem, as visualized in Recogito. 

January 10, 49 BCE: Revising The Tale Of Caesar’s Crossing of the Rubicon

It was a great trip to the combined annual meeting for the Society for Classical Studies and Archaeological Institute of America (SCS-AIA) in Toronto, but it definitely put me behind on my blogging schedule. No matter! Welcome to a new year, pious readers, and with it comes a reflection on immutable actions over at Forbes. For the 2,066th anniversary of Julius Caesar crossing the Rubicon river (and thus essentially declaring civil war with Rome), I spoke to Robert Morstein-Marx, an ancient historian and Caesar expert at the University of California-Santa Barbara. Prof. Morstein-Marx is hard at work on a book about Caesar that revises many of the narratives surrounding the dictator.

This includes the mythical depiction of the general pausing on his horse at the ford of the Rubicon river in northern Italy in order to soak in the gravitas of the moment. In reality? Caesar’s troops had already crossed the rather small river and Caesar himself later crossed in a wagon rather than on horseback. However, eyewitnesses such as Asinius Pollio and then the poet Lucan used the geography of the moment for dramatic effect. This post is about the timeline that led up to the “alea iacta est” (the die [=dice not dye] is tossed) moment and the revising of a myth, for sure, but it is also about how historians employ geography to show other boundaries: legal, emotional, and ethical ones.

…Just think of all the inaccuracies later attached to Washington’s crossing of the Delaware in 1776!


Approximate location of the Rubicon river in northern Italy. Map provided by the Pelagios Project’s Peripleo under a CC-BY-SA.

A note about the primary sources: A timeline and the primary readings for most of these events can be found at the Attalus website for the year 49 BCE.

Numbering The Stars: Remembering the Contributions of Medieval Muslim Astronomers And Catalogers

This week over at the Forbes blog, I discuss the International Astronomical Union (IAU)‘s publication of an official catalog of 227 star names. The list was published this week in order to further standardize how we reference stars and constellations, since each one has had numerous monikers in Greek, Roman, Chinese, Arabic and many other languages over the many millenia that people have been studying the stars.

Although I laud the IAU’s attempt to streamline naming, I was dismayed to see that in the section of the website recounting the history of cataloguing of the stars, the association begins with the western astronomers that worked during the European Renaissance. By crediting Johann Bayer’Uranometria atlas of 1603 as the first such popular catalog of stars, they in fact omit the great contributions of ancient astronomers and Muslim celestial cataloguers in particular. I attempt to remedy that by recounting a short history of Muslim mathematicians and astronomers (as well as a few forgotten medieval women).

I am also posting a list of digital resources and manuscripts below that I consulted for this article, so that you too can investigate the myriad contributions of Muslim scientists via the manuscripts themselves:


Ursa major (الدب الأكبر) as viewed on a celestial globe (upper) and as viewed in the sky (lower) (Or 5323, f.8v). Image via the British Library and is in the Public Domain.

  1. Library of Congress, “Astronomical Innovation in the Islamic World”
  2. Marika Sardar, “Astronomy and Astrology in the Medieval Islamic World
  3. Abd-al-Rahman al-Sufi, “Tables from the Book of the constellations of the fixed stars (Kitab suwar al-kawakib) in a Latin translation,” via the British Library
  4. Ursula Sims-Williams, “Arabic scientific manuscripts go live in Qatar Digital Library,” Asian and African Studies Blog, via the British Library.
  5. The J. Paul Getty Museum, “Astronomical and Medical Miscellany: Toledan Constellation Tables; De Dispositione Aeris; De Prognosticationibus Egritudinem; etc., English, late 14th century, shortly after 1386Ms. Ludwig XII 7
  6. Elly Decker, Illustrating the Phaenomena: Celestial cartography in Antiquity and the Middle Ages. Oxford: Oxford University Press, 2012.

I am grateful for the help given to me by the University of Iowa’s Special Collections librarians. Map librarian Paula Balkenende pulled a number of celestial maps for me and then gave me a special look at Lanciani’s Forma Urbis Romae–just for kicks.