The first official land survey of Detroit was conducted by Aaron Greeley. After the US gained control of the Michigan Territory they needed an official record of land holdings. Greeley surveyed land in Detroit from 1809 to 1810 and his records were approved by Congress in 1812 which made his survey map the authoritative source of land claims.
However, Greeley’s survey did not include informal land grants or awards. As a result many Southeast Michigan residents appealed to Congress and eventually around 100 land claims were approved. Yet the boundaries of land claims continued to be contested for years following.