Wikipedia:Selected anniversaries/September 30

September 30: Independence Day in Botswana (1966).

• 1399 – The Duke of Lancaster deposed Richard II to become Henry IV of England, merging the Duchy of Lancaster with the crown.

• 1791 – The Magic Flute, the last opera composed by Wolfgang Amadeus Mozart, premiered at Theater an der Wien in Vienna, Austria.

• 1939 – World War II: General Władysław Sikorski (pictured) became Prime Minister of the Polish government-in-exile.

• 1966 – Seretse Khama became the first President of Botswana when the Bechuanaland Protectorate gained independence from the United Kingdom.

• 1980 – Xerox, Intel and Digital Equipment Corporation published the first Ethernet specifications, currently the most widespread wired local area network (LAN) technology.

More anniversaries:

• September 29
• September 30
• October 1