Such was his impact on breaking the bonds between Britain and the EU that after Johnson was forced to announce Thursday that he would step down, the news brought little public jubilation in EU circles.
Instead, there was just the numb acceptance of the inevitable and resignation that things will never be the same.
``I will not miss him,'' French finance minister Bruno Le Maire said, highlighting an open disdain unseen since the Europeans welcomed the US election loss of Donald Trump in 2020. And while trans-Atlantic relations picked up quickly since the arrival of President Joe Biden, don't expect anything similar with a new British leader, politicians and experts said.
``Even with a new prime minister, I believe there will likely be few changes in the British government's position`` on the main Brexit issues causing current divisions, said David McAllister, the leading EU legislator dealing with the United Kingdom.
Guy Verhofstadt, who was the top EU parliamentarian during the whole Brexit divorce proceedings, said Johnson's impact was such there is little to no chance another Conservative prime minister could steer a fundamentally different course.
``No one is under any illusion that Johnson's departure from Downing Street solves any of the underlying problems in the UK.-EU relationship,'' Verhofstadt wrote in an opinion piece for The Guardian. ``The damage done by the outgoing prime minister, through the project that he instrumentalized to achieve power, lives on.''
The United Kingdom was always a halfhearted EU member since joining the bloc in 1973. When Johnson joined the Brussels press corps some three decades ago, he often enthralled his home readership with stories that had two fundamental elements: they put the EU in the darkest of lights, and they had little connection to reality.
As a Conservative politician, he threw his weight in the 2016 referendum on the UK's EU membership behind arguments to leave the bloc.
Johnson used his breezy manner and jokey style to sell the benefits of withdrawing from the EU, sometimes disregarding the facts. He was key to the Brexit campaign's victory in the cliff-edge 2016 Brexit referendum vote.
Yet disdain never ran deeper than earlier this year when he started moves toward unilaterally rewriting parts of the post-Brexit deal he signed with the 27-nation bloc.
The agreement set up a special system in Northern Ireland, which is part of the UK, so trade with the Republic of Ireland, an EU member, could go on without setting up a physical border.
``I was there face to face with him. Line for line, comma for comma, and he doesn't want to respect it,'' EU chief Brexit negotiator Michel Barnier reminisced Friday, still showing bafflement at Johnson's tactics.
``The reputational damage has been huge to a country and society which has long been proud of its deep culture of `My word is my bond' without even a written contract, let alone an international treaty,'' said Michael Emerson of the Center for European Policy Studies.
The bill to unilaterally break the agreement on trade in Northern Ireland is still in the House of Commons, and some lingering hope is left that London might step back from the brink.
``They have this law in the Parliament, so they are doing steps in that direction. But they have not crossed the line,'' said Jan Lipavský, the foreign minister of Czechia, which holds the EU presidency and is more widely known in English as the Czech Republic.
Yet a quick glance at the likely contenders to take over doesn't inspire hope for any fundamental change since it includes several Conservatives who have spent years steeping in Johnson's confrontational Brexit strategies.
``If you look at possible successors, there is no one who will fundamentally break with the Brexit line,'' said Rem Korteweg of the Clingendael Institute in The Hague, Netherlands. ``The Conservative Party has a dominant Brexit core that you will have to convince to become prime minister.''
Although the first years of Brexit have yielded anything but the bounty Johnson promised, any possible quest to return the UK to the EU is also as good as out of the question, with the main opposition Labour Party now centering to make the best of the Brexit situation instead.
Not that the EU would even want to welcome back the country with open arms.
With Ukraine, inflation-spurred economic issues and migration problems, ``their plate is full,'' Korteweg said. ``They are really not waiting for talks with the British, who will be looking for exceptions and exemptions anyway,'' he said.
Barnier, who led the EU in Brexit talks for years, doesn't see it happening either.
``It is not an issue at hand,'' Barnier said on Sud Radio. ``Very frankly, what we need is a state of mind where the British government respects the treaties it negotiated.''