20th century

The 20th (twentieth) century began on January 1, 1901 (MCMI), and ended on December 31, 2000 (MM). The 20th century was dominated by significant events that defined the modern era: Spanish flu pandemic, World War I and World War II, nuclear weapons, nuclear power and space exploration, nationalism and decolonization, technological advances, and the Cold War and post-Cold War conflicts. These reshaped the political and social structure of the globe.