Labour has ended more than 40 years of Conservative rule in Wandsworth in a humiliating defeat for Boris Johnson.
The southwest London borough, known as Margaret Thatcher's 'favourite council' has been Tory controlled since 1978.
But in a night of high drama at the election count, Labour captured enough seats to secure a majority.
The authority now has 35 Labour councillors, 22 Conservatives and one independent.
London mayor Sadiq Khan, himself a Wandsworth resident, was on hand to witness his party's historic win.
New leader Simon Hogg promised to continue Wandsworth's record of low council tax but also pledged to build 1,000 council homes.
"We are going to build a compassionate council that truly listens and keep that same low council tax," said Councillor Hogg.
"But when we were calling around on voters we didn't even have to raise partygate, we didn't have to mention Boris Johnson.
"People have formed their own views on this Government, so I am afraid it is time for change at the top as well," he added.
Defeated council leader Ravi Govindia said the election was tough and the national politics impacted the result.
"There were concerns about the cost of living, there were concerns about partygate but there were also concerns about the fuel crisis ands we were successful on focusing people's attention back to what I am responsible for," Mr Govindia said.
"We did all we could to help ease the crisis for people where we could.
"People always say we ran a great council, they love what we do, and they would reward us, but it seemed on the day not," he added.
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