On 4 July 1943, at 23:07, moments after take-off from Gibraltar Airport, Liberator II aircraft AL523 with General Władysław Sikorski on board, crashed into the Mediterranean Sea.
On 4 July 1928, the founding congress of the Sybiraks' Association was held at the Warsaw University of Technology.
On the night of 6 to 7 July (24/25 June old style) 1866, 5,000 kilometres east of their homeland, a group of January insurgents sent to Baikal for penal labour stirred up a rebellion, disarmed their guards and tried to forge an escape route to Mongolia.