- **Date of Independence:** July 4, 1776 (as part of the original 13 colonies declaring independence from Britain) - **Date of Annexation to [[United States of America (USA)]]:** December 3, 1818 (21st state to join the Union) - **Population (2025):** 12.78 million - **GDP (2025):** $1.132 trillion - **Largest City:** Chicago (2.61 million) - **State Capital:** Springfield (117,000) - **Historical Note:** Known as the "Prairie State" and "Land of Lincoln." Home to Presidents [[Abraham Lincoln]], [[Barack Obama]], and [[Ronald Reagan]] (birthplace). Chicago is the third-largest U.S. city and major transportation hub. Center of Great Migration from the South. Major industrial and financial center with diverse economy including agriculture, manufacturing, and services.