Putnam County is a county located in the U.S. state of Ohio. As of the 2010 census, the population was 34,499. Its county seat is Ottawa. The county was created in 1820 and later organized in 1834. Its name is in honor of Israel Putnam, who was a hero in the French and Indian War and a general in the American Revolutionary War.
34,499 people lived in Ottawa in 2010