The Kingdom of Great Britain, officially Great Britain, was a sovereign state in western Europe from 1 May 1707 to 31 December 1800. The state came into being following the Treaty of Union in 1706, ratified by the Acts of Union 1707, which united the kingdoms of England and Scotland to form a single kingdom encompassing the whole island of Great Britain and its outlying islands. It did not include Ireland, which remained a separate realm. The unitary state was governed by a single parliament and government that was based in Westminster. The former kingdoms had been in personal union since James VI, King of Scots, became King of England and King of Ireland in 1603 following the death of Queen Elizabeth I, bringing about the "Union of the Crowns". Also after the accession of King George I to the throne of Great Britain in 1714, the kingdom was in a personal union with the Electorate of Hanover.

The early years of the unified kingdom were marked by Jacobite risings which ended in defeat for the Stuart cause at Culloden in 1746. Later on in 1763, victory in the Seven Years' War led to the dominance of the British Empire, which was to become the foremost global power for over a century and later grew to become the largest empire in history.

...
Wikipedia