On this day: 26 March

Byzantine emperor Maurice proclaimed his son Theodosius as his co-emperor.

First Eid al-Fitr celebration.

Pope John XIX crowns Conrad II as Holy Roman Emperor.

Saladin (depicted on coin) was inaugurated as vizier of Egypt.

The crown of Aragon and the crown of Castile agree in the Treaty of Almizra on the limits of their respective expansion into al-Andalus.

Reconquista: The Muslim city of Algeciras surrendered after a 21-month siege and was incorporated into the Kingdom of Castile.

The Siege of Algeciras, one of the first European military engagements where gunpowder was used, comes to an end.

Guru Amar Das becomes the Third Sikh guru.

Utrecht University is founded in the Netherlands.

The Royal Academy of Turku, the first university of Finland, is founded in the city of Turku by Queen Christina of Sweden at the proposal of Count Per Brahe.

The Safavid Empire began a four-year occupation of the Ottoman city of Basra on the Persian Gulf.

Safavid government troops take control of Basra.

The Boston Gazette printed a cartoon coining the term "gerrymander", named after Governor Elbridge Gerry (pictured), who approved the legislation that created oddly shaped electoral districts.

An earthquake devastates Caracas, Venezuela.

The Book of Mormon is published in Palmyra, New York.

The elections of Commune council of the Paris Commune are held.

Perceiving that the Canadian government was failing to protect their rights, the Métis people led by Louis Riel began the North-West Rebellion.

First Balkan War: After a five-month siege, Bulgarian and Serbian forces captured the Ottoman city of Adrianople.

The Vancouver Millionaires win the 1915 Stanley Cup Final, the first championship played between the Pacific Coast Hockey Association and the National Hockey Association.

The German Social Democratic Party is founded in Poland.

Swissair is founded as the national airline of Switzerland.

Ho Chi Minh Communist Youth Union is founded in Vietnam.

Nationalist forces began their final offensive of the Spanish Civil War, at the end of which they controlled almost the entire country.

World War II: The Battle of Iwo Jima ends as the island is officially secured by American forces.

Jonas Salk announced the successful test of his polio vaccine on a small group of adults and children.

The United States Army launches Explorer 3.

The African Regroupment Party is launched at a meeting in Paris.

Ten thousand people gather for one of many Central Park be-ins in New York City.

South Vietnamese President Nguyễn Văn Thiệu implements a land reform program to solve the problem of land tenancy.

East Pakistan, then a province of Pakistan, declares its independence from Pakistan to form Bangladesh; the Bangladesh War of Independence begins.

A group of peasant women in Chamoli district, Uttarakhand, India, surrounded trees in order to prevent loggers from felling them, giving rise to the Chipko movement.

The Biological Weapons Convention, the first multilateral disarmament treaty banning the production of an entire category of weapons, entered into force.

Anwar al-Sadat, Menachem Begin and Jimmy Carter sign the Egypt–Israel peace treaty in Washington, D.C.

A groundbreaking ceremony for the Vietnam Veterans Memorial is held in Washington, D.C.

Argentina, Brazil, Uruguay and Paraguay sign the Treaty of Asunción, establishing Mercosur, the South Common Market.

Around 200,000 to 300,000 Taiwanese demonstrate in Taipei in opposition to the Anti-Secession Law of China.

A prototype of the Tesla Model S, one of the most influential electric cars in history, was unveiled.