March 15

Roman dictator Julius Caesar is assassinated by a group of senators on the Ides of March, a pivotal moment in the fall of the Roman Republic.

A group of Roman senators, including Brutus and Cassius, stabbed Julius Caesar to death in the Theatre of Pompey, fearing his accumulating power threatened the Republic. Rather than restoring republican governance, the assassination triggered years of civil war that ultimately led to the rise of Caesar's heir, Augustus, as emperor.

Maine is admitted as the 23rd U.S. state, part of the sectional balance struck by the Missouri Compromise.

Maine was admitted to the Union as a free state as part of the Missouri Compromise, which simultaneously allowed Missouri to enter as a slave state to preserve the sectional balance in the Senate. The arrangement temporarily eased tensions over slavery's expansion but merely postponed the deeper national reckoning.

Tsar Nicholas II abdicates the Russian throne, ending the 304-year Romanov dynasty.

Facing mutinying troops and losing the support of his generals amid the February Revolution, Tsar Nicholas II abdicated the throne, ending over three centuries of Romanov rule. His abdication led to a provisional government that itself was overthrown by the Bolsheviks later that year, and the former tsar's family was executed in 1918.

Fuad I becomes King of Egypt after the country gains nominal independence from Britain.

Britain granted Egypt nominal independence while retaining control over defense, foreign affairs, and the Suez Canal, and Sultan Fuad I took the title of King. The arrangement left considerable British influence intact, fueling continued nationalist agitation that eventually led to fuller independence decades later.

Nazi Germany occupies the remainder of Czechoslovakia, violating the earlier Munich Agreement.

German troops occupied the remaining Czech territories of Bohemia and Moravia after Hitler summoned Czechoslovak President Emil Hacha to Berlin and coerced his capitulation, violating the earlier Munich Agreement's guarantees. The move exposed the futility of Western appeasement and pushed Europe closer to full-scale war.

Iran's parliament votes to nationalize the country's oil industry, previously controlled by a British company.

Iran's parliament voted to nationalize the Anglo-Iranian Oil Company's holdings, asserting control over the country's vast petroleum resources previously dominated by British interests. The move, championed by Prime Minister Mohammad Mossadegh, led to a British-led boycott and eventually a 1953 coup that removed him from power.

President Lyndon B. Johnson addresses Congress advocating for the Voting Rights Act amid the Selma civil rights crisis.

President Lyndon B. Johnson addressed a joint session of Congress, invoking the phrase "we shall overcome" and calling for passage of comprehensive voting rights legislation in the wake of the violent Selma marches. Congress passed the Voting Rights Act months later, outlawing discriminatory voting practices across the South.

A treaty granting full sovereignty to a reunified Germany comes into effect, formally ending postwar Allied occupation.

A treaty between the two German states and the four World War II Allied powers came into force, granting a reunified Germany full sovereignty and ending the residual occupation rights the Allies had held since 1945. The agreement completed the formal process of German reunification that began with the fall of the Berlin Wall.

Mass protests begin in Syria, part of the wider Arab Spring, eventually escalating into a prolonged civil war.

Protests against Bashar al-Assad's government began in the southern Syrian city of Deraa following the detention and torture of teenagers who had painted revolutionary graffiti. The demonstrations, part of the broader Arab Spring, escalated into a devastating civil war that continued for over a decade.

A gunman kills 51 people at two mosques in Christchurch, New Zealand, in a livestreamed terrorist attack.

A gunman opened fire on worshippers at two mosques in Christchurch, New Zealand, killing 51 people in an attack he livestreamed online. The massacre, motivated by white supremacist ideology, prompted New Zealand to swiftly enact sweeping gun control legislation within weeks.