All times in UTC ·
Dashed edge = started before, or continues beyond, this day
Events on Friday 31 March 1939 1
1939British guarantee to PolandChamberlain pledges to defend Polish independenceNeville Chamberlain told the House of Commons that Britain and France would support Poland if its independence were threatened. The guarantee followed the German occupation of Prague. It committed Britain to go to war when Germany invaded Poland.