From Ohio History Central
Townships are relatively small pieces of land (usually no larger than thirty-six square miles). They are created to designate landownership or to establish a form of local government. Within the United States, there are two different types of townships.
The first type of township is a survey township. These townships were created as the United States expanded. The federal government used survey townships to survey and sell public land, as well as to designate property ownership. For example, the Land Ordinance of 1785 established survey townships in what would eventually become Ohio. As the states and Native Americans relinquished lands in the Northwest Territory to the federal government, government surveyors were to divide the territory into individual townships. Each township was to be square. Each side of the square was to be six miles in length, and the completed square would include a total of thirty-six square miles of territory. The township would then be divided into one-square mile sections, with each section encompassing 640 acres. Each section received its own number. Section sixteen was set aside for the use of the public schools. The federal government reserved sections eight, eleven, twenty-six, and twenty-nine to provide veterans of the American Revolution with land bounties for their service during the war. The government would sell the remaining sections at public auction. The minimum bid was 640 dollars per section or one dollar for each acre of land in each section.
From time to time, townships were surveyed that measured only five miles on a side or which had other variations on the usual form of thirty-six one square mile sections.
The other type of township is known as a civil township. Typically, a board of township trustees oversees the township. The major issues that a township government addresses are cemetery maintenance, trash collection, road upkeep, and snow removal. Civil townships are most common in rural areas, but even large cities sometimes expand around townships or parts of townships. Commonly townships are annexed into a municipality as a town or city develops and expands. For example, Mill Creek Township in Hamilton County, Ohio no longer exists, as several cities, most notably Cincinnati, absorbed the township by annexation, acquisition or other means.
In 2000, 16,504 civil townships existed in the United States. These townships existed in twenty states, primarily states in the Northeast or in the Midwest. Over the course of Ohio's history, at least 1,340 townships have existed within the state.