4 April in World History

On 4 April 1949, 12 European and North American countries signed the North Atlantic Treaty, founding NATO. The organisation was established by 10 European countries (the United Kingdom, Belgium, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway and Portugal), the USA and Canada, during the Cold War as a counterbalance to the USSR and other communist states. Latvia joined NATO in 2004.

On 4 April 1975, Bill Gates and Paul Allen founded Microsoft in Albuquerque, New Mexico. Today Microsoft is the world's largest computer software company by revenue.

On 4 April 1968, Martin Luther King - a leading activist in the African-American civil rights movement - was assassinated in Memphis, Tennessee, USA. He employed the principles of non-violent resistance advocated by Gandhi. In 1964 he was awarded the Nobel Peace Prize.

On 4 April 1973, the World Trade Center was opened in New York. At the time, the World Trade Center towers were the tallest buildings in the world. On the morning of 11 September 2001, two hijacked aircraft struck the World Trade Center approximately 18 minutes apart. The entire complex was destroyed, and a total of 2,752 people perished.

If you know of a significant fact or event in Latvia or elsewhere in the world on this date, please add it in the comments!