The controversial Kharkiv Pact (Russian Ukrainian Naval Base for Gas Treaty) is signed in Kharkiv, Ukraine, by Ukrainian president Viktor Yanukovych and Russian president Dmitry Medvedev; it was unilaterally terminated by Russia on March 31, 2014. Date: April 21, 2010 Read more on Wikipedia → 📅 Other events on April 21 📅 Events on this…

Two trains are involved in a head-on collision near Sloterdijk, Amsterdam, in the Netherlands, killing one person and injuring 116 others. Date: April 21, 2012 Read more on Wikipedia → 📅 Other events on April 21 📅 Events on this day in 2012 📅 On This Day (Today)

Eight bombs explode at churches, hotels, and other locations in Sri Lanka on Easter Sunday, killing at least 269. Date: April 21, 2019 Read more on Wikipedia → 📅 Other events on April 21 📅 Events on this day in 2019 📅 On This Day (Today)

Indonesian Navy submarine KRI Nanggala (402) sinks in the Bali Sea during a military drill, killing all 53 on board. Date: April 21, 2021 Read more on Wikipedia → 📅 Other events on April 21 📅 Events on this day in 2021 📅 On This Day (Today)

Pierre and Marie Curie refine radium chloride. Date: April 20, 1902 Read more on Wikipedia → 📅 Other events on April 20 📅 Events on this day in 1902 📅 On This Day (Today)

Opening day of competition in the New South Wales Rugby League. Date: April 20, 1908 Read more on Wikipedia → 📅 Other events on April 20 📅 Events on this day in 1908 📅 On This Day (Today)

Nineteen men, women, and children participating in a strike are killed in the Ludlow Massacre during the Colorado Coalfield War. Date: April 20, 1914 Read more on Wikipedia → 📅 Other events on April 20 📅 Events on this day in 1914 📅 On This Day (Today)

World War I: Manfred von Richthofen, a.k.a. The Red Baron, shoots down his 79th and 80th victims, his final victories before his death the following day. Date: April 20, 1918 Read more on Wikipedia → 📅 Other events on April 20 📅 Events on this day in 1918 📅 On This Day (Today)

The Soviet government creates the South Ossetian Autonomous Oblast within the Georgian SSR. Date: April 20, 1922 Read more on Wikipedia → 📅 Other events on April 20 📅 Events on this day in 1922 📅 On This Day (Today)

Twenty Jewish children used in medical experiments at Neuengamme are killed in the basement of the Bullenhuser Damm school. Date: April 20, 1945 Read more on Wikipedia → 📅 Other events on April 20 📅 Events on this day in 1945 📅 On This Day (Today)