SINN Féin dealt a devastating blow to the SDLP by outpolling the party in its Foyle heartland for the first time.
New assembly candidate Elisha McCallion also managed to top the poll ahead of SDLP leader Colum Eastwood and was elected on the first count, comfortably over quota.
Derry has long been regarded as an SDLP citadel, being home to its current leader and best known figure, former MP John Hume.
While Sinn Féin had been edging closer to its nationalist rival in recent elections, there is huge symbolic significance in finally coming out on top in Foyle.
Following the second count there was further good news for the party as veteran assembly member Raymond McCartney passed the quota, with Mr Eastwood following at the third stage.
Former Stormont minister Mark H Durkan was also returned soon afterwards, with the DUP's Gary Middleton eventually overcoming outgoing People Before Profit MLA Eamonn McCann for the final seat.
The SDLP did actually increase its vote in Foyle as well as its share of the vote, which was up almost two per cent.
However, Sinn Féin saw its share rocket from 28.5% last year to 36.6%.
The party put some of the success down to the record of former Foyle MLA and deputy first minister Martin McGuinness, who retired from electoral politics earlier this year on health grounds.
She was replaced on the ticket by former Derry and Strabane mayor Ms McCallion.
Mr McCartney said there was "absolutely no doubt Martin McGuinness energised our people".
"I think at the doors people were saying ‘we know why he did what he had to do’ and they appreciated what he has done over many, many years and so people came out and we reaped the benefit of it today."
In the SDLP camp, party workers were decidedly downbeat.
Mr Eastwood acknowledged that Sinn Féin had a good day but said he was pleased his party's vote increased by more than 2,000.
“This is an election in the middle of a political context nobody could have imagined, a poisonous, divisive context that just didn’t suit us and we still increased our vote and still retained our seats,” he said.
"We’re not into symbolism; we’re into the number of seats we have and we’ve got the same number of seats.”
Mr McCann also put the loss of the seat he held for just 10 months down to the polarisation of Stormont politics.
“It is a disappointing outcome - there is no question about that. We'll be up on Monday morning trying all over again,” he said.
Mr Middleton, meanwhile, said it was important that the DUP secured the only unionist seat in Derry.
“It is important that unionism has a confidence and has a voice there to raise their issues and take their concerns to Stormont,” he said.
