Discovery of the cosmic microwave background radiation by Robert Woodrow Wilson and Arno Penzias. Cosmic microwave background radiation (CMB radiation) is the faint electromagnetic radiation…
Tag: 20 May
20 May 1875
Signing of the Metre Convention by 17 nations leading to the establishment of the International System of Units. The Metre Convention, signed on May 20,…
20 May 1645
Yangzhou massacre: The ten day massacre of 800,000 residents of the city of Yangzhou, part of the Transition from Ming to Qing. The Yangzhou Massacre…
20 May 1521
Ignatius of Loyola is seriously wounded in the Battle of Pampeluna. The Battle of Pampeluna, also known as the Siege of Pampeluna, took place in…
20 May 1980
In a referendum in Quebec, the population rejects, by 60% of the vote, a government proposal to move towards independence from Canada.
20 May 1873
Levi Strauss and Jacob Davis receive a U.S. patent for blue jeans with copper rivets. [rdp-wiki-embed url=’https://en.wikipedia.org/wiki/Levi_Strauss’]
20 May 1940
The first prisoners arrive at a newly built concentration camp at Auschwitz. Auschwitz, also known as Auschwitz-Birkenau, opened in 1940 and was the largest of…
20 May 1969
The Battle of Hamburger Hill during the Vietnam War ends. Hamburger Hill was the scene of an intense and controversial battle during the Vietnam War….
20 May 1940
The first prisoners arrive at the concentration camp at Auschwitz. The in famous sign “Arbeit macht frei” (work set you free) on the entry gate…