The Scottish National Party, the SNP, won half the votes in Scotland but took almost all the seats there.
It becomes the third biggest party in a Westminster parliament likely to again be led by David Cameron’s Conservatives.
Labour, which has traditionally always done very well in Scotland, took a hammering there.
And, under Britain’s first-past-the-post constituency-based electoral system, a vote for the SNP favoured Cameron’s Tories in the battle for control in London.
The SNP won 56 of 59 parliamentary seats in Scotland, up from just six at the last election in 2010.
The massive size of the SNP’s contingent at Westminster relative to its puny share of the vote in Britain as a whole, breathes new life into the debate about Britain shifting to a proportional representation electoral system. Such a system would not deliver the SNP more seats in Westminster than three other smallish parties - the Liberal Democrats, the Greens and the eurosceptic UK Independence Party - combined.
The SNP’s historic landslide in Thursday’s elections is all the more astonishing as it comes just months after voters rejected the party’s call for independence from the rest of Britain by 55% in a referendum.
For Nicola Sturgeon, who took over as SNP leader after the September referendum,  “this is a watershed, historic election”. But Sturgeon has given conflicting signals about whether she will promise another referendum in the SNP manifesto for elections to the Scottish parliament in 2016.
Yesterday she said independence was not the immediate priority. “There will only be another referendum when people in a Scottish parliament election vote for a proposition. There is no proposal on the table right now,” she said.
Despite Sturgeon’s words, her opponents say the SNP’s aim is to push for a second referendum. Not all SNP voters are pro-independence, however, and polls show that the sentiment on that issue has not changed much since last year’s referendum.
How to respond to the SNP challenge is already on the lips of Cameron, on the cusp of a second five-year term that he has already said will be his last.
He promised to “govern on the basis of governing for everyone” in Britain and to “bring our United Kingdom together” by delivering on the devolution promises he made last year, just before Scots voted in a referendum against breaking away from the United Kingdom.
London mayor Boris Johnson, returning to Westminster and a likely future candidate to succeed Cameron, is also keen to patch up the union.
“There has to be some kind of federal offer (to Scotland),” he said after winning a London seat. “I think even most people in the SNP ... do not want to throw away absolutely everything.”
During the campaign, Labour’s Ed Miliband had also recognised the massive constitutional importance of the vote in Scotland.