Overview
The United States industrialized rapidly, expanded across the Pacific, and became the world’s leading economic and military power during the 20th century. Canada grew from a self-governing dominion into a fully independent nation, while Mexico passed through the long Porfiriato and the upheaval of its 1910 Revolution.
Key developments
Immigration, urbanization, and technological change transformed daily life, and the three economies grew closely linked, formalized by NAFTA in 1994 and its successor the USMCA. The century also brought the two world wars, the civil rights movement, and deep social change.
End and transition
Today North America’s three large nations remain economically integrated and globally influential, facing shared challenges of migration, inequality, and climate change. Their history continues the long story that began some fifteen thousand years ago.