From 2011, Cassandra Pybus on using The Book of Negroes and the digital resource Black Loyalists:

“The Book of Negroes is an extraordinary historical resource, a meticulous list drawn up by the British authorities between May and November 1783, in which they recorded the personal details of some 3,000 African Americans evacuated from New York. The great majority of these people were originally enslaved workers who had defected to the British and were now leaving America as free people. The most significant thing about the Book of Negroes is that most people are recorded with surnames that allow them to be tracked through the archives. It is organized by ship with each person given a name, in many cases with a surname, age, brief description, owner’s name, date of absconding, geographic location and, where appropriate, the name of a loyalist sponsor. Even though the surnames of listed individuals are often misheard, the ages are wildly inaccurate and the time of absconding is ambiguous, we simply don’t have demographic data like this about enslaved people in the eighteenth century in any other source….”

Read it all: Black Loyalists and “The Book of Negroes” | Not Even Past