It was created from Albany County on March 24, 1772, and was named for William Tryon, the last provincial governor of New York.
[2] The Tryon County Courthouse, built in 1772–1773, was listed on the National Register of Historic Places in 1972.
[3] The Tryon County Jail, also built in 1772–1773, was listed on the National Register of Historic Places in 1981.
[3] The county was divided into five districts: Mohawk, Palatine, Canajohorie, German Flatts, and Kingsland.
In December 1780, the results of a census stated that the number of uncultivated farms was 1200 and that 354 families had abandoned and had fled the county.