The United Kingdom became a member of the European Communities on 1 January 1973. Those communities developed, via a long and winding road, into the modern-day European Union.
The many twists and turns of the often turbulent relationship between the UK and the EU need not be traced here and doubtless many histories will be written.
UK membership ceased on 31 January 2020 (previous post) and the UK entered a transition period lasting for the remainder of 2020. The transition period masked the impact of Brexit.
Leaving the EU was a break