The interview, broadcast in 2010 on the French-language television station Tele-Quebec, was resurrected a day earlier in news reports from Sun Media and immediately seized upon by the Conservatives.
Trudeau apologized during a stop in Vancouver, insisting he was really just making a clumsy attack on Prime Minister Stephen Harper, who rose to power as an MP from Calgary.
"I was wrong to relate the area of the country that Mr. Harper is from ... with the policies that he has that don't represent the values of most Canadians," Trudeau told a gathering of reporters.
"It was wrong to use a shorthand to say Alberta when I was really talking about Mr. Harper's government, and I'm sorry I did that."
The Conservatives have used the interview as fodder to attack Trudeau and his party, particularly in Calgary, where a federal byelection scheduled for next week has become more competitive than expected.
When asked how the controversy might affect his party's byelection chances, Trudeau largely ignored the question, instead accusing the Conservatives of resorting to attacks in a moment of panic over the prospect of losing in Calgary-Centre.
In a 2010 appearance on the program Les francs-tireurs, Trudeau said: "Canada isn't doing well right now because it's Albertans who control our community and socio-democratic agenda. It doesn't work."
He also said Canada would be better served if there were more Quebecers than Albertans in charge, arguing "the great prime ministers of the 20th Century" have come from Quebec.
On Friday, Trudeau said his comments about the lack of Quebecers — and the abundance of Albertans — in power was an attempt to urge voters in Quebec to vote for a national party capable of forming government.
"The interview I gave was very much focused on telling Quebecers how very important it was to stop voting for the Bloc Quebecois and to start engaging once again with the national discourse in Canada," he said.
The Conservatives resumed their attacks Friday, with MPs in Parliament taking turns assailing Trudeau and the Liberals.
The Tories were eager to link the Trudeau interview with comments from David McGuinty, an Ontario MP who resigned as the Liberal party's natural resources critic earlier this week after accusing Conservative MPs from Alberta of being "shills" for the oil industry. McGuinty said those MPs should "go back" to Alberta.
"We knew, of course, that this anti-Alberta attitude was deeply held in the Liberal party but we did not know how close to the surface it was," Public Works Minister Rona Ambrose, who represents the Alberta riding of Edmonton-Spruce Grove, told Parliament.
Several Conservative MPs, including Ambrose, called on Trudeau to resign as the Liberal party critic for post-secondary education, youth and amateur sport.
Blaine Calkins, a Conservative whose riding of Wetaskiwin is south of Edmonton, nearly accused Trudeau and McGuinty of sparking a national crisis. Calkins introduced a motion that said the pair's comments were so serious that Parliament's natural resources committee, which he sits on, should stage hearings to highlight the economic benefits of Alberta's energy sector.
Alberta Premier Alison Redford also joined in, after she was asked about Trudeau's comments at the close of a premiers meeting in Halifax.
"It's important for us to be able to know that we can have confidence that people that want to sit in our federal government aren't going to pit one part of the country against another," Redford told a news conference on Friday.
"I think that's a pretty important value, not just for Albertans but for all Canadians."
It's not the first time Trudeau has been forced to explain controversial comments about Quebec. Earlier this year, he suggested he might support Quebec separation if he felt Canada had truly adopted the values of Harper's Conservatives.
Earlier this week, before the latest controversy erupted, Trudeau acknowledged his tendency to put his foot in his mouth was his Achilles heel.
"I try to be very, very open, I try to be very authentic, and that regularly gets me in trouble," he said during the town hall-style event in Victoria.
"I think an awful lot (before I speak), but what I often don't think about is how people can take portions of my answer or choose to misinterpret my answer and run with it. ... I know I have to learn that a little bit more."Suggest a correction