Labour ended the Conservatives' 100-year hold of Hexham amid a series of major successes across the region.
Joe Morris beat Guy Opperman by 3,000 votes to become the Northumberland seat's first ever Labour MP.
The Conservatives also lost North Northumberland, where incumbent Anne-Marie Trevelyan was beaten by Labour's David Smith.
Labour also won seats in Newcastle, Gateshead and North and South Tyneside, with Reform finishing second across the region.
Mr Morris said it was a "historic night", adding: "It’s an immense honour and an immense privilege, but also an immense responsibility.
"I’m really excited to start delivering."
Mr Opperman, who had been Hexham's MP since 2010, said it was too early for a "post-mortem" examination.
"Clearly these are very difficult circ*mstances," he said, adding: "We’re obviously going to have to go away and reflect."
David Smith, the newly elected Labour MP for North Northumberland, said: "There’s been a massive desire for change, and fatigue and exhaustion over the last 14 years."
On the issue of dualling the A1, he said he would "not make any promises" but would "fight for it".
Ms Trevelyan - who served as both transport and international development secretary - said if he did not sort out the road she would "make his life daily hell".
She said the Conservatives needed to "look forward", adding: "We'll come together, sit down, mourn the loss of talented colleagues and start to rebuild what our core values are."
Newcastle's three seats were held by Labour, with Reform coming second in Newcastle East and Wallsend and Newcastle Central and West.
Chi Onwurah, who has held her seat for Labour, said: "Today has been a day of unity and an overwhelming call for change in our community.
"Our future as a community, as a nation, will be so much brighter together.
"Now is the time to come together for a better Newcastle."
Washington and Gateshead South was held for Labour by Sharon Hodgson who secured 48% of the vote, with Reform coming second, while Jarrow and Gateshead East was held by Labour's Kate Osborne and Gateshead Central and Whickham by Labour's Mark Ferguson.
Labour's Emma Lewell-Buck, who retained her South Shields seat, said it had been a massive night for her and the party and she would be happy to do any job in a new Labour government.
She also said she would be having a few fizzy ones with her team to celebrate.
Emma Foody, the new Labour MP for the newly created Cramlington and Killingworth seat, said the area's communities had "voted overwhelmingly for change".
"It's been 14 long years for our communities," she said.
"The scale of the challenge is great. We will repay that trust."
Sir Alan Campbell retained his place as Labour MP for Tynemouth, a seat he has held since Tony Blair’s 1997 landslide victory.
There was a positive reaction from residents in Hexham on Friday morning.
Ellie Duncan, 20, said she was "so excited" and hoped improving public transport would be a top priority, while Lauren Blissett, 46, said the town turning Labour was a "big moment".
"As a nurse I'm hoping to see some real changes under Labour," Ms Blissett said, adding: "I'm on my way to work now, we'll probably all have a quick celebration before clocking in."
Graham Morton, 73, said he couldn't bring himself to vote Labour and opted for the Liberal Democrats, but was "pleased to see the back of this Conservative government".
By Richard Moss, BBC Political editor, North East & Cumbria
It was a night of Labour triumph and Conservative disaster in the North East and Cumbria.
In the end they just avoided a complete wipeout, but only just. Deputy Party Chairman Matt Vickers’ win in Stockton West avoided that ignominy.
It leaves the Tories with fewer MPs here than at any time in the party’s modern history.
And it was not just the gains from 2019 that slipped away.
Hexham – Conservative for 100 years – was taken by Labour for the first time.
In North Northumberland, David Smith’s victory was perhaps even more remarkable. He was only selected a few days before Rishi Sunak called the election and yet overturned a majority of almost 18,000 and removed Conservative minister Anne-Marie Trevelyan.
Then there was Cumbria. The party went into the election having an effective majority in all the county’s five redrawn seats. They left it without a single MP there. Labour took four, Lib Dem Tim Farron the fifth, overcoming unfavourable boundary changes to win a 20,000-plus majority.
Conservatives had been hopeful that the Tees Valley area would be a happier hunting ground as candidates looked to tie themselves to Ben Houchen – the mayor who won across the area just two months ago. And the party’s vote did hold up slightly better, but it didn’t prevent all but Stockton West slipping away.
Scalps included former cabinet member Sir Simon Clarke, and current Levelling Up Minister Jacob Young. The party’s two County Durham seats also went to Labour.
But the night was also notable for a surge in the Reform UK vote that put them in second place in a string of constituencies. Results they will look to build on in the next two sets of local elections, with the hope of pushing for wins whenever the seats are contested again.
This though was largely a mirror image of 2019. Then it was the Conservatives pushing into previously unconquered territory, this time Labour was making new ground.
But there is a warning there. Tory wins then were founded, at least in part, on promises to "level up" the region. Voters have clearly decided that wasn’t delivered. Labour have promised change and hope. If they don’t deliver then the party cannot be sure the same fate may await, and Reform UK in particular could be waiting to capitalise.
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