1521: Spanish conquistadors under Hernán Cortés capture Aztec Emperor Cuauhtémoc in Tenochtitlan marking the end of the Aztec Empire

1536: Buddhist monks from Kyōto’s Enryaku Temple set fire to 21 Nichiren temples throughout Kyoto in the Tenbun Hokke Disturbance. (Traditional Japanese date: July 27, 1536).

1642: Dutch astronomer Christiaan Huygens discovers Mars’ southern polar cap

1788: Prussia joins Anglo-Dutch alliance to form Triple Alliance to prevent spread of Russo-Swedish War of 1788-90

1937: Second Sino-Japanese War: Japanese forces begin the Battle of Shanghai, a conflict that will last 3 months and involve 1 million troops

1942: The ‘Manhattan Project’ commences, under the direction of US General Leslie Groves: its aim – to deliver an atomic bomb

Source: Onthisday.com