New York County Boundries in the US Census In 1790 there were few upstate counties. Most of central NY (Onondaga, Oswego, Oneida, etc) was included within Montgomery Cy. The Albany area (Albany, Columbia, Rensselaer, etc) was all in Albany Cy. NY Cy included some of the S Bronx. The remainder was in Westchester Cy. Queens Cy included today's Nassau Cy. In 1800 Onondaga Cy had been formed, including today's Cortland Cy and SW Oswego Cy. Oneida Cy included much of today's Jefferson Cy and the remainder of Oswego. In 1810 Onondaga was unchanged. Oneida included 1800's Oswego. Jefferson and Lewis Cy had been formed with approximately the present boundries. In 1820 Onondaga, Oswego, Oneida, Jefferson and Lewis counties boundries were essentially as they are today. From 1800 to 1870 NY Cy included some of S Bronx. The remainder was in Westchester Cy. Queens Cy included today's Nassau Cy. Source: Thorndale and Dollerhide "Map Guide to the U.S. Federal Census Records"