After years of buildup to Brexit, a drama that obsessed and divided a nation, Britain was poised to leave the European Union on Thursday night, not with a bang but with a recorded New Year’s Eve light show on the BBC. With a newly emergent, highly transmissible variant of the coronavirus surging, even the most zealous Brexiteers were likely to mark the launch of “Global Britain” while tucked safely indoors, under the government’s “Tier 4” stay-at-home orders, which now apply to 75 percent of the population of England, alongside tough measures in Wales, Scotland and Northern Ireland.

British health officials begged people not to have parties. “Covid loves a crowd,” they warned. Finally free from Brussels bureaucrats, post-Brexit Britons aren’t free to go to the pub, because eateries and taverns are closed. And while they have “taken back control” of their borders, Britons find themselves facing travel restrictions from dozens of countries hoping to keep the coronavirus variant out.

Britain officially — on paper — left the European Union on Jan. 31, and there was plenty of Union Jack waving in Parliament Square that night. But not much changed during the 11-month transition period that followed. The dramatic shift in the relationship between Britain and Europe — the culmination of a fight that has brought down multiple prime ministers — happens on Thursday at 11 p.m. London time, midnight in Brussels, when Britain leaves the bloc it helped establish almost five decades ago.

A border sign welcomes passengers arriving at Heathrow Airport in west London on Dec. 31.

On Thursday evening, Prime Minister Boris Johnson released a short video in which he acknowledged that many people “will be only too happy to say goodbye to the grimness of 2020,” the year in which “the government was forced to tell people how to live their lives, how long to wash their hands, how many households could meet together.”