Stillwater is a city in Washington County, Minnesota, directly across the St. Croix River from the state of Wisconsin. The population was 18,225 at the 2010 census. It is the county seat. Stillwater is part of the Twin Cities Metro Area.
On July 29 and September 29, 1837, treaties were signed between the US government and the local Ojibwa and Dakota nations that allowed settlement in the St. Croix Valley. The town was founded by settlers drawn by the area's then-abundant lumber and river traffic, making it one of Minnesota's oldest towns, preceding Minneapolis by several years. Stillwater was officially incorporated as a city on March 4, 1854 (the same day as St. Paul).
Stillwater is often called Minnesota's birthplace. In 1848, a territorial convention that began the process of establishing Minnesota as a state was held in Stillwater, at the corner of Myrtle and Main Streets. Minnesota officially became a territory in 1849 and a state in 1858.
As more evidence of Stillwater's importance at the time, the convention selected three leading Minnesota cities as locations for three important public institutions: Minneapolis got the University of Minnesota, Saint Paul became the capital, and Stillwater was chosen as the site of the territory's first prison. The Minnesota Territorial Prison was opened in 1853.
Lumbering was the predominant industry in the St. Croix River Valley in the second half of the 19th century, and for many years logs were sent down the St. Croix, collected at the St. Croix Boom Site two miles upstream of Stillwater, and processed in Stillwater's many sawmills. Steamboats were used most widely from 1860 to 1890, and a few are still used for entertainment today.