When Leave won the EU referendum, Dominic Cummings, the mastermind of the victory, celebrated by mounting a table and punching a tile from the ceiling of his campaign war room.

When Brexit itself happened on Friday night, Cummings responded not with cheers but tears.

At a party in 10 Downing Street, as the 11pm deadline passed, the assistant to the prime minister and the most feared man in government took to the microphone wearing tracksuit bottoms and black trainers and was lost for words as emotion overcame him.

The man once branded “a career psychopath” by David Cameron, clutched a hand across his face and sought to compose himself. Eventually, he managed to say: “Lots of people in this room know what happened. Thank you.”