On March 29

British prime minister Theresa May invoked Article 50 of the Treaty on European Union, formally beginning the United Kingdom's withdrawal from the European Union.

The first same-sex marriages in England and Wales took place following the passage of the Marriage (Same Sex Couples) Act 2013.

Islamist separatists of the Caucasus Emirate detonated two bombs on the Moscow Metro, killing 40 people and injuring 102 others.

The Chamoli earthquake, one of the strongest to hit the foothills of the Himalayas in more than 90 years, killed at least 100 people.

Queen Elizabeth II granted royal assent to the Canada Act 1982, which ended any remaining constitutional dependence of Canada on the United Kingdom by a process known as patriation.

Dick Beardsley and Inge Simonsen jointly won the Men's Elite Race and Joyce Smith won the Women's Elite Race in the inaugural London Marathon.

Jeff Beck released Blow by Blow, his most successful album in the U.S., reaching the top five and selling over one million copies.

A group of farmers in the Chinese province of Shaanxi discovered a vast collection of terracotta statues (pictured) depicting the armies of Qin Shi Huang, the first emperor of China.

NASA's Mariner 10 became the first space probe to make a flyby of Mercury.

The funeral of Yuri Gagarin, the first man in space, began in Moscow with tens of thousands of people in attendance.

The King and I, a musical about Mongkut of Siam by Rodgers and Hammerstein, premiered on Broadway.

Second World War: British and Australian ships defeated Italian Regia Marina vessels at the Battle of Cape Matapan.

The North American Regional Broadcasting Agreement to define technical standards for AM band radio stations came into effect.

The Knights of Columbus, the world's largest Catholic fraternal service organization, was founded by Michael J. McGivney in New Haven, Connecticut, U.S.

American Civil War: The Appomattox campaign opened with the Battle of Lewis's Farm, in which the Confederate Army of Northern Virginia was forced into a series of retreats that would culminate in their surrender.

Authorities held an inquest at New Town, Tasmania, into the deaths of a woman and two children who were fatally poisoned after eating smooth toadfish.

Joaquín de Oreamuno led a coup d'état that overthrew Rafael Francisco Osejo, attempting to restore allegiance to the Mexican Empire.

German astronomer Heinrich Wilhelm Matthias Olbers discovered Vesta, the brightest asteroid and second-most massive body in the asteroid belt.

William Matthews was ordained as the first Catholic priest born in British America.

Wars of the Roses: The Yorkists defeated the Lancastrian army at the Battle of Towton, allowing Edward IV to secure the English throne.