Set off by Gov. Cass in 1822, this county took its name from the French "La Pierre", a translation of the Indian name for the Flint River. Settlers began to arrive in 1828. The county seat, founded in 1831, was also named Lapeer. Organization of the county government took place in 1835. This courthouse, built in 1839, is the oldest one still in use in Michigan. Farming is the county's principal economic activity, and it was here that the first local Grange in Michigan was founded in 1872.