Osceola County, Michigan: History
When established by the Michigan Legislature on April 1, 1840, it was named Unwattin County, after Chief Unwattin of the local Ottawa people. As a representative of the Ottawa nation, he participated in negotiations for the Treaty of Washington (1836) that granted a vast expanse of Michigan to the US Federal Government. The name was changed March 8, 1843, to Osceola, after the Seminole chief who achieved renown in Florida.
The county was initially attached for administrative purposes to Ottawa County. In 1855, it was attached to Mason County; in 1857, to Newaygo County; and in 1859, to Mecosta County.
As the population increased, separate county government was organized in 1869, with Hersey designated as the county seat. Reed City became the official county seat in 1927. The county was developed initially for harvesting and processing lumber, and many European Americans came to work in lumbering and the mills.