The city is adjacent to Monroe Charter Township but politically independent. The city is located 17 miles north of Toledo, Ohio, and 25 miles south of Detroit.
* Founded in 1785 as Frenchtown, it is the third oldest European settlement in Michigan.
* The River Raisin runs through the city. The Battle of Frenchtown, one of the bloodiest in the War of 1812, was fought near the mouth of the river. It was the largest conflict in Michigan and the River Raisin Battlefield is being considered for inclusion in the National Parks System.
* The City of Monroe and Monroe County were named for President James Monroe, who visited Michigan Territory in 1817.
* Monroe is known for ties to General George Armstrong Custer. He spent much of his boyhood with his half-sister and his brother-in-law in Monroe, where he attended school and is honored by a statue in the center of town. The statue has been the focus of many protests over the years due to Custer's role in oppressing Native American people. He married Elizabeth Clift Bacon (1842-1933) on February 9, 1864. She was born in Monroe to Daniel Stanton Bacon and Eleanor Sophia Page. They had no children.
* Downtown Monroe is home to the Monroe County Historical Museum.