January 20: Day of Nationwide Sorrow in Azerbaijan (1990); Inauguration Day in the United States (2025); Martin Luther KingJr. Day in the United States (2025) Roller coasters1265 Simon de Montfort summoned local representatives to the Palace of Westminster to attend a parliament, now considered to be the forerunner of the House of Commons of England.1840 WilliamII became King of the Netherlands after his father WilliamI abdicated the throne.1885 LaMarcus Adna Thompson, sometimes called the "Father of Gravity", patented the roller coaster (pictured).1945 World WarII: In an operation that took nearly two months to complete, Germany began the evacuation of at least 1.8million people from East Prussia in anticipation of the advancing Soviet Red Army.2018 A group of Taliban gunmen attacked and took hostages at the Inter-Continental Hotel in Kabul, Afghanistan, sparking a 12-hour battle that left at least 21 people dead.Sebastian Mnster (b.1488)Agnes Mary Clerke (d.1907)Yolanda Gonzlez (b.1961)Sophie, Duchess of Edinburgh (b.1965)More anniversaries: January 19January 20January 21ArchiveBy emailList of days of the yearAbout