The Roman conquest of Britain began, leading to significant cultural and political changes.
The Normans conquered England, reshaping its feudal structure and monarchy.
The Kingdom of England and the Kingdom of Scotland united under the Treaty of Union.
The Acts of Union incorporated the Kingdom of Ireland, creating the United Kingdom of Great Britain and Ireland.
Most of Ireland seceded to form the Irish Free State, altering the UK structure.
The Royal and Parliamentary Titles Act created the present-day United Kingdom of Great Britain and Northern Ireland.