Dubuque is a city in Dubuque County, Iowa, United States, and its county seat. The population was 59,667 at the 2020 census. Settled in 1788 and chartered in 1833, Dubuque is the oldest city in Iowa. It was named after French-Canadian trader and miner Julien Dubuque. The city lies along the Mississippi River at the convergence of the Iowa, Illinois, and Wisconsin borders, a region locally known as the Tri-State Area.