Miami is a city in and the county seat of Ottawa County, Oklahoma, United States, founded in 1891. Lead and zinc mining were established by 1…Miami is a city in and the county seat of Ottawa County, Oklahoma, United States, founded in 1891. Lead and zinc mining were established by 1918, causing the area's economy to boom. This area was part of Indian Territory. Miami is the capital of the federally recognized Miami Tribe of Oklahoma, after which it is named; the Modoc Tribe of Oklahoma, the Ottawa Tribe of Oklahoma, the Peoria Tribe of Indians, and the Shawnee Tribe. As of the 2020 census, the population was 12,969.