TUESDAY, Dec. 9, 2025

536-Byzantine General Belisarius enters Rome while the Ostrogothic garrison peacefully leaves the city, returning the old capital to its empire

1212-Frederick II (later also Holy Roman Emperor) crowned King of Germany in Mainz

1941-China declares war on Japan, Germany & Italy

1948-U.N. General Assembly unanimously approves Convention on Genocide

1968-Douglas Engelbart demonstrates in "The Mother of All Demos" the computer system NLS (oN-Line System) to a live audience in San Francisco, showcasing for the first time the mouse, word processing, windows, hypertext links, video conferencing, real-time collaboration, and other modern computing concepts

1967-Nicolae Ceaușescu becomes President of Romania (overthrown in 1989)

1990-Lech Wałęsa wins the first direct presidential election in Poland

1992-U.S. Marines and allied nations launch an amphibious and airborne operation in Mogadishu, Somalia to restore order to the war-torn nation. Authorized by U.N. Security Council Resolution 794 passed on Dec. 3.