Baldwin City is a city in Douglas County, Kansas, United States about 12 miles (19 km) south of Lawrence and 15 miles (24 km) west of Gardner. As of the 2010 census, the city population was 4,515. The city is home to Baker University, the state's oldest four-year university.
Baldwin City began as a trail stop on the Santa Fe Trail named Palmyra. The small community consisted of a harness shop, blacksmith, hotel, lawyer, drug store, two doctors and a tavern. In 1858, a group of Methodist ministers gathered at Kibbee Cabin and founded Baker University. Palmyra bought land to the south for the university and surrounding city. The first post office was established in June, 1857.
A main benefactor of the community was John Baldwin and the town was named in his honor. Baldwin built a saw mill which was at present-day Fifth and Indiana Streets. Baldwin City was incorporated on September 22, 1870.