On 01 May 1707, the Acts of Union joined the Kingdoms of England and Scotland into the Kingdom of Great Britain.
They had shared a single monarch for a hundred years since Queen Elizabeth I died childless, and James VI of Scotland became James I of England. The Acts of Union combined their two parliaments into one.
Many Scots were unhappy with the union, but as historian Simon Schama said, "What began as a hostile merger, would end in a full partnership in the most powerful going concern in the world ... it was one of the most astonishing transformations in European history."