On this day: 7 April

First Corpus Juris Civilis, a fundamental work in jurisprudence, is issued by Eastern Roman Emperor Justinian I.

Holy Roman Emperor Charles IV charters Prague University.

Felix V abdicates his claim to the papacy, ending the reign of the final Antipope.

Ferdinand Magellan arrives at Cebu.

Francis Xavier leaves Lisbon on a mission to the Portuguese East Indies.

After a conclave lasting eighty days, the College of Cardinals elected Fabio Chigi as Pope Alexander VII.

Premiere performance of Bach's St John Passion, BWV 245, at St. Nicholas Church, Leipzig.

End of Burmese–Siamese War (1765–1767).

Settlers establish Marietta, Ohio, the first permanent settlement created by U.S. citizens in the recently organized Northwest Territory.

Russo-Turkish war (1787–1792): Greek privateer Lambros Katsonis loses three of his ships in the Battle of Andros.

The French First Republic adopts the kilogram and gram as its primary unit of mass.

The Mississippi Territory is organized from disputed territory claimed by both the United States and the Spanish Empire. It is expanded in 1804 and again in 1812.

German composer Ludwig van Beethoven premieres his Third Symphony, at the Theater an der Wien in Vienna.

Lewis and Clark Expedition: The Corps of Discovery breaks camp among the Mandan tribe and resumes its journey West along the Missouri River.

Pedro II became emperor of the Empire of Brazil.

An Arctic expedition led by Norwegian explorer Fridtjof Nansen (pictured) reached 86°13.6′N, almost three degrees beyond the previous Farthest North latitude.

The Algeciras Conference gives France and Spain control over Morocco.

Prohibition in the United States is repealed for beer of no more than 3.2% alcohol by weight, eight months before the ratification of the Twenty-first Amendment to the United States Constitution. (Now celebrated as National Beer Day in the United States.)

Italy invades Albania.

Booker T. Washington becomes the first African American to be depicted on a United States postage stamp.

The National Football League makes helmets mandatory.

Ioannis Rallis becomes collaborationist Prime Minister of Greece during the Axis Occupation.

The Soviet Union annexes East Prussia as the Kaliningrad Oblast of the Russian Soviet Federative Socialist Republic.

The United Nations established the World Health Organization to act as a coordinating authority on international public health.

The Rodgers and Hammerstein musical South Pacific, based on Tales of the South Pacific by James Michener, opened on Broadway.

United States President Dwight D. Eisenhower gives his "domino theory" speech during a news conference.

Francoist Spain agrees to surrender its protectorate in Morocco.

IBM announces the System/360.

Representatives of the National Congress of American Indians testify before members of the US Senate in Washington, D.C., against the termination of the Colville tribe.

The Internet's symbolic birth date: Publication of RFC 1.

Vietnam War: President Richard Nixon announces his decision to quicken the pace of Vietnamization.

Communist forces overran the South Vietnamese town of Lộc Ninh.

Uganda–Tanzania War: Tanzanian forces defeated Ugandan troops and their Libyan allies at the Battle of Entebbe, opening the way for an advance on the Ugandan capital, Kampala.

During STS-6, astronauts Story Musgrave and Don Peterson perform the first Space Shuttle spacewalk.

Soviet Defense Minister Dmitry Yazov orders the Soviet withdrawal from Afghanistan.

John Poindexter is convicted for his role in the Iran–Contra affair. In 1991 the convictions are reversed on appeal.

NASA's 2001 Mars Odyssey (artist's conception pictured), the longest-surviving continually active spacecraft in orbit around a planet other than Earth, launched from Cape Canaveral.

Iraq War: U.S. troops capture Baghdad; Saddam Hussein's Ba'athist regime falls two days later.

Haitian president Jean-Bertrand Aristide demands reparations of $21 billion from France for the Haitian independence debt.

First release of Git distributed version control system.

Mass protests begin across Moldova under the belief that results from the parliamentary election are fraudulent.

The Israel Defense Forces use their Iron Dome missile system to successfully intercept a BM-21 Grad launched from Gaza, marking the first short-range missile intercept ever.

U.S. President Donald Trump orders the 2017 Shayrat missile strike against Syria in retaliation for the Khan Shaykhun chemical attack.

COVID-19 pandemic: China ends its lockdown in Wuhan.

COVID-19 pandemic: Acting Secretary of the Navy Thomas Modly resigns for his handling of the COVID-19 pandemic on USS Theodore Roosevelt and the dismissal of Brett Crozier.

COVID-19 pandemic: The Centers for Disease Control and Prevention announces that the SARS-CoV-2 Alpha variant has become the dominant strain of COVID-19 in the United States.

Ketanji Brown Jackson is confirmed for the Supreme Court of the United States, becoming the first black female justice.