From Separate Kingdoms to the United Kingdom: The Union of England and Scotland

England and Scotland did not directly become the "United Kingdom." The process occurred in two stages:

1. 1707 – Kingdom of Great Britain

The Acts of Union 1707 merged the Kingdom of England (including Wales) and the Kingdom of Scotland into a single state: the Kingdom of Great Britain. One parliament (Westminster), one monarch, but separate legal (Scots law) and religious (Church of Scotland) systems.

2. 1801 – United Kingdom of Great Britain and Ireland

The Acts of Union 1800 (effective 1 Jan 1801) united Great Britain with the Kingdom of Ireland, creating the United Kingdom of Great Britain and Ireland.

3. 1922 – Present Name

After Irish independence (1922), the state was renamed the United Kingdom of Great Britain and Northern Ireland (1927).

So: England + Scotland → Great Britain (1707) → + Ireland → UK (1801) → – most of Ireland → current UK (1922).