Complex sentence: In late 1827 Hamilton served during the Winnebago War in the volunteer Illinois Militia as a captain in command of a company raised in Galena, Illinois known as the Galena Mounted Volunteers.
Split into simpler sentences: In late 1827 Hamilton served during the Winnebago War in the volunteer Illinois Militia as a captain. Hamilton commanded a company raised in Galena, Illinois known as the Galena Mounted Volunteers.