Wikipedia:Selected anniversaries/September 23
- 1459 - The Battle of Blore Heath, the first major battle of the Wars of the Roses, was fought at Blore Heath, in Staffordshire, England. At least 3,000 men died.
- 1846 - Neptune, the eighth planet from the sun, was discovered by French astronomer Urbain Jean Joseph Le Verrier, British astronomer John Couch Adams and German astronomer Johann Gottfried Galle.
- 1932 - Hejaz and Nejd were unified and became the Kingdom of Saudi Arabia, with Abdul Aziz bin Abdul Rahman ibn Faisal Al Saud as the first monarch and Riyadh as the capital city.
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