After several years doing standard historical research, my work evolved into something unique and very straightforward: I turn historical resources into data and I map it. My first such effort was the

DC Historical Building Permits Database.

Because I was gathering so much data that was screaming to be mapped, I learned GIS. The Permits Database thereby evolved into


I deal mostly with the built environment, but thought that theĀ application of GIS would enlighten on another aspect of the city’s history, so I co-founded

Mapping Segregation in Washington DC.

Along the way, the DC Historic Preservation Office wanted me to do some other

Historical GIS.

More recently I’ve turned my attention to the founding of the city and its life and development in the 19th Century. I call this new endeavor

Mapping Early Washington.

Because online interactive maps make the best public interfaces for online historical resources, I am developing the

DC Oral History Access Map.

These “developer subdivisions” are available as a layer on HistoryQuestDC.