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On March 4, 1845, the Ohio government authorized the creation of Defiance County. The county was originally parts of Williams, Henry, and Paulding Counties. Residents named the county after Fort Defiance, a fortification constructed by General Anthony Wayne�s men prior to the Battle of Fallen Timbers in 1794. Fort Defiance was also important to defending Ohio from invasion by British soldiers and their native allies during the War of 1812.
Defiance County is located in northwestern Ohio. The county�s western boundary helps to form the border between Indiana and Ohio. Defiance County is predominantly rural, with only one percent of the county�s 411 square miles consisting of urban areas. The county seat is Defiance, site of Fort Defiance. With a population of 16,465 people, Defiance was the county�s largest community in 2000. The next largest urban area was Hicksville, with a population of 3,649 people in 2000. Like most of Ohio�s predominantly rural counties, Defiance County experienced a decline in population between 1990 and 2000, reducing the number of residents to 39,500 people down from 40,115. The migrants typically leave the rural areas, seeking more social and economic opportunities in Ohio�s larger cities. The county averages ninety-six people per square mile.
The largest employers in Defiance County are manufacturing businesses, especially a General Motors powertrain assembly plant that hires 2,550 workers. Sales positions, service industries, farming, and government careers rank second, third, fourth and fifth respectively. In 1999, the per capita income in the county was almost twenty-five thousand dollars, with 7.1 percent of the people living in poverty.
Most voters in Defiance County claim to be independents, yet in recent years, they have supported Republican Party candidates at the national level.
Among Defiance County�s more prominent residents was Pontiac, the Ottawa chieftain that led Pontiac�s Rebellion following the French and Indian War. The county also is home to Defiance College.