1823

1823 was a year in the early 19th century characterized by political upheaval and the consolidation of independence in the Americas, as well as significant diplomatic realignments in Europe. Across the western hemisphere, former colonies pursued constitutional arrangements and republican institutions, while in North America the United States asserted a regional policy that would shape diplomatic practice for generations.

On December 2, 1823, President James Monroe announced the Monroe Doctrine, a defining U.S. policy drafted largely by Secretary of State John Quincy Adams. It warned European powers against further colonization in the Americas and stated that the United States would oppose such interference while remaining neutral toward existing colonial regimes. The doctrine established a long-running principle of U.S. hemispheric influence.

In Mexico, liberal opposition to Emperor Agustín de Iturbide culminated in the Plan of Casa Mata and Iturbide’s abdication on March 19, 1823. The abdication ended the short-lived Mexican monarchy and paved the way for the formation of a republic, which would be formalized with the 1824 Constitution.

In Europe, France dispatched the Hundred Thousand Sons of Saint Louis to restore Ferdinand VII to absolute power in Spain, ending the Liberal Triennium and reasserting monarchic authority. The intervention reflected the broader reaction against liberal constitutions that followed the Napoleonic era, shaping Spanish politics for years to come.

Beyond these events, 1823 saw ongoing momentum in Latin American independence movements and continued debates over constitutional governance, monarchy, and modernization across the Atlantic world.