The Eastern historical district of Pike County is made up of Detroit Township which is bordered on the east by the Illinois River. The town of Detroit located within the township was founded in 1837 by Peter H. Lucas and named by him after the post office which had been established years before. Soon after Henry Neeley added the town plat which was referred to as the Neeley Addition consisting of all the part of Detroit north of Main Street.

At its peak Detroit contained two stores, a drug store, two blacksmith shops, one wagon manufacturer, one shoemakers shop, a millinery store and a broom factory. Along with these places of business the town contained three physicians and four church organizations. The citizens erected a fine two story brick schoolhouse that employed two teacher.

The town of Florence, Illinois was founded in 1836 by the Florence Company which was made up of Pittsfield, Illinois businessmen. The primary founders were Austin Barber, Robert R. Greene, William Ross, Thomas Worthington and James Davis.

The town is the oldest settlement in Detroit Township and was laid out on the west bank of the Illinois River with the intention to be used for river transportation for the town of Pittsfield. In 1836 the State of Illinois passed funding for road improvements in Pike County. Some of the funds were spent turning the road from Pittsfield to Florence into a plank road. Many years later the road was graveled.

The land that Florence was established on was owned by John Roberts originally before it was obtained by the Florence Company. William Ross and Stephen Gay kept the first store. By 1836 a sawmill was established by the founders of the Florence Company. Later that mill would be converted into a steam powered flour mill in 1842. In the early pioneer days Florence was known as Augusta. The town grew and prospered until 1849 when gold was discovered in California. From that time on the town began to dwindle in size.