The UK (United Kingdom) got its name following the Act of Union in 1801, which politically united the Kingdom of Great Britain and the Kingdom of Ireland, resulting in the new state called the United Kingdom of Great Britain and Ireland.
Prior to 1801, "Great Britain" was itself formed by the union of the kingdoms of England and Scotland in 1707. The term "United Kingdom" transformed from a geographically descriptive and sometimes aspirational phrase into a firm political reality with the Act of Union.
Here's a breakdown:
- Pre-1707: Separate kingdoms of England and Scotland.
- 1707: Act of Union creates the Kingdom of Great Britain.
- 1801: Act of Union unites Great Britain and the Kingdom of Ireland, creating the United Kingdom of Great Britain and Ireland.
The name has changed slightly over time with the departure of most of Ireland, now becoming the United Kingdom of Great Britain and Northern Ireland.