Labour have won an emphatic majority on the new Cumberland Council.
The party gained 30 out of 46 seats, with the Conservatives getting just seven.
The new unitary authority contains the districts of Carlisle, Allerdale and Copeland.
It will formally take over responsibility for all services in April 2023, when the existing county and district councils will be abolished.
The newly-elected councillors will initially serve on a shadow authority, overseeing the transition.
Labour - 30
Conservative - 7
Liberal Democrats - 4
Independent - 3
Green Party - 2
It had been thought that the Conservatives had a reasonable chance of winning control of Cumberland themselves.
The Tories had gained significant ground in the area in recent years, including winning the high-profile parliamentary by-election in Copeland in 2017, and the Workington seat at the 2019 general election.
This result is a major boost for Labour's hopes of rebuilding past strength in the so-called 'Red Wall'.
It comes after their party leader Sir Keir Starmer paid campaign visits to Carlisle and Workington last week.
Cllr Helen Tucker is Cockermouth North, Labour: "I'm just amazed. Overwhelmed. I think this is sending a message to the powers that be in Westminster that the population is not happy."Sam Brown from the Conservatives said: "It was good to see strong Conservative areas are still staying strong Conservative. We did have some failures in areas and it gives us an opportunity to rebuild."
Results for the new Westmorland and Furness Council, as well as Dumfries & Galloway and Scottish Borders authorities are due to be declared later on Friday.