Missouri Compromise Map 1821 - U.S. Slave and Free States Distribution #2241995 (License: Personal Use)

The map depicts the United States following the Missouri Compromise of 1820, with the 36°30′ parallel marking the boundary for future slavery expansion. It highlights key regions including the Arkansas Territory (open to slavery), Michigan and Illinois (free), and the unorganized territory north of Missouri. Spanish possessions and British North America are also shown for geopolitical context.

Used in educational history pages, textbooks, and digital archives to explain antebellum U.S. territorial policy and the roots of sectional conflict; matches user intent for historical research, teaching resources, or understanding pre-Civil War geography.