All times in UTC ·
Dashed edge = started before, or continues beyond, this day
Events on Thursday 1 January 1801 1
1801Act of Union creates the United Kingdom of Great Britain and IrelandGreat Britain and Ireland merge into a single kingdomOn 1 January 1801 the Act of Union took effect, merging the Kingdom of Great Britain and the Kingdom of Ireland into the United Kingdom of Great Britain and Ireland. The Irish Parliament in Dublin was abolished and Irish members began sitting at Westminster. A new Union Flag combining the crosses of England, Scotland, and Ireland came into use.