1129 people die in the worst building collapse disaster in modern history. The building was used by clothing factories producing garments for western markets, highlighting the disastrous working conditions in the industry.
Joseph Ratzinger is inaugurated as Pope Benedict XVI. The German was considered a particularly conservative Pope - quite unlike his successor, Pope Francis.
The Hubble Space Telescope is launched into Earth orbit. Unhindered by the impurities and distortions of Earth's atmosphere, the 2.4 meter (7.9 feet) aperture telescope has delivered some of the most spectacular images of the far reaches of the Universe.
Vietnam War: American General William Westmoreland says in a news conference that the enemy had "gained support in the United States that gives him hope that he can win politically that which he cannot win militarily.".
The Suez Canal reopens after the Suez Crisis. The conflict between Egypt on the one hand and France, the United Kingdom and Israel on the other, erupted in October 1956 when Egypt announced that the canal will be nationalized.
The Easter Rebellion begins in Dublin, Ireland. Although unsuccessful, the uprising was an important symbolic event leading to the establishment of the Republic of Ireland.
The Ottoman Empire begins its systematic extermination of Armenians. An estimated 1 million people were killed in the Armenian Massacres during and after World War I. The event is considered one of the first genocides in modern history.