Jack Layton: Canadian politician who became leader of the opposition after revitalising the NDP

Jack Layton, a career politician, was the charismatic leader of the New Democratic Party (NDP), Canada's new opposition party. With his boundless energy and folksy yet feisty no-nonsense approach, he had battled cancer and a hip replacement to lead his left-of-centre party to an historic victory in last May's federal election. He had brought hope and optimism to federal politics and was arguably at the height of his political career.

The union-backed NDP took a record 103 seats, up from a previous 37, and crushed Michael Ignatieff's Liberal Party (34 seats) to become the official opposition in the Commons for the first time in their 50-year history. Further history was made in French-speaking Quebec, where the party stunned Canadians and won 59 of the province's 75 seats, making Layton the first Anglophone to enjoy such unprecedented success; this devastating victory effectively eliminated the Bloc Québécois (a party devoted to Quebec's separation) from Parliament, leaving it without status as a recognised party.

During the election campaign, thanks to his friendly and outgoing personality, Layton was portrayed as "Smilin' Jack" and "Le bon Jack" in the media, or just "Jack" on his party's campaign advertisements. He was a rassembleur, and, with his relaxed approach, bringing people together was one of his great talents; he had a real ability to connect with his fellow Canadians.

Layton and the NDP had changed their campaign approach, eschewing anger and attack ads, which focus groups knew women voters disliked. The NDP shed the last of their overtly socialist positions and adopted a platform aimed more at attracting middle-class voters, which angered some of the party's left wing. Layton and his team learned from previous elections and professionalised the NDP; they made it a much more research-driven, voter-focused and tactically innovative political organisation. He offered voters an alternative political agenda to the Conservatives that stepped outside the mantra of tax-cutting and balanced budgets and talked about better pensions, education, healthcare and the wrongs of economic inequality – as well as the environment and climate change. The NDP also embarked upon the largest advertising campaign in its history, focusing on the Government's healthcare record.

Born into a political family in Montreal, Canada on 18 July 1950, John Gilbert "Jack" Layton was the son of Doris Elizabeth (née Steeves), a grand-niece of William Steeves, a Father of Confederation, and Robert Layton, a Progressive Conservative MP and cabinet minister. His grandfather was Gilbert Layton, a cabinet minister in the 1930s Union Nationale government of Maurice Duplessis in Quebec, who subsequently resigned over the government's lack of support for Canada's participation in the Second World War. His great-grandfather, Philip Layton, who emigrated from England, was a blind piano dealer in Montreal and established the Montreal Association for the Blind.

Layton grew up in the affluent, mainly English-speaking suburb of Hudson. Politics was in his blood. From student-council president at Hudson High School he went on to study political science at McGill University, Montreal, before completing his doctorate at York University, Toronto. In 1969, prior to his university education, Layton had married his high-school sweetheart, Sally Halford, with whom he had two children, Mike and Sarah.

In 1969/70, he was the Prime Minister of the Quebec Youth Parliament. He later served as a professor at Ryerson University, Toronto, teaching city politics to students from its journalism school. Layton enjoyed many interests, including cycling, was an accomplished musician and also wrote a number of books.

A Quebec native, Layton was an activist and community organiser in Toronto, campaigning on issues such as Aids and violence against women. He was elected to Toronto City Council in 1981 and spent 20 years as a thorn in the side of conservative mayors. He continued to work tirelessly on behalf of the poor and homeless and was a champion of environmental and transport issues. He ran twice for mayor of Toronto and lost in 1991 after being criticised for living in subsidised housing and for opposing Toronto's ultimately failed bid for the 1996 Summer Olympics.

Layton became leader of the NDP in January 2003; in 2004 he became an MP and led the NDP to a 15 per cent popular vote, its highest in 16 years, although it only gained 19 seats in the House of Commons. He then led the party to 29 federal seats in the 2006 election, which increased to 37 in 2008.

For all his history-making during the May 2011 elections, Layton knew his real challenge lay ahead, keeping his caucus united and presenting the NDP as a government-in-waiting rather than as the socialist hordes; the first part was a prerequisite for the second. Layton knew that caucus management was his biggest challenge: bringing the Quebecers together with the party's 44 MPs from the rest of Canada, who had very different ideas.

However, within weeks of his greatest triumph, on 25 July, Layton announced that after having apparently beaten prostate cancer, he had now been diagnosed with a "non-prostate cancer" which required him to temporarily step aside as leader of the NDP in order to fight it. His announcement and his rapid weight loss and deteriorating physical condition shocked Canadians.

Layton received praise from all quarters of the political spectrum. He was said by many to have brought a sense of decency, integrity and optimism to an arena where many were turned off by cynicism and scepticism in politics. Canada's Prime Minister, Stephen Harper, said that Layton will be remembered "for the force of his personality and his dedication to public life. We have all lost an engaging personality and a man of strong principles."

Former Prime Minister Brian Mulroney called Layton an "honourable, decent, loyal" man. "I think history will remember his historic achievement of transforming the NDP from, really, a prairie party, in many ways, into a genuine national party with tremendous achievement in Quebec." Indeed, Layton will be remembered for transforming a dysfunctional four-party minority House into a functional three-party majority Parliament – as well as for his effective, down-to-earth brand of progressive politics.

His rise from the relative obscurity of Toronto's municipal government to become, in electoral terms, the most successful national leader in the 78-year history of the CCF (Co-operative Commonwealth Federation, a socialist party formed during the Great Depression)-NDP franchise was remarkable.

In an open letter, Layton addressed Canadians: "My friends, love is better than anger. Hope is better than fear. Optimism is better than despair. So let us be loving, hopeful and optimistic. And we'll change the world."

Martin Childs

Jack Layton, politician: born Montreal, Canada 18 July 1950; married first 1969 Sally Halford (divorced 1983, one son, one daughter), second 1988 Olivia Chow; died Toronto, Canada 22 August 2011.