When Jack Layton told Canadians on July 25 that he was facing a new battle with cancer, he made sure to inject notes of hope and optimism into his sombre news.

He said he had always tried to bring those qualities to his work in politics and he would apply them to the personal battle he was undertaking, following a new cancer diagnosis he received a week earlier.

The 61-year-old leader of the Official Opposition announced he was stepping away from the job, a role he coveted and had won only two months earlier, to concentrate on his cancer treatment so he could come back to Parliament in the fall, ready to fight for Canadian families.

Layton died early Monday at home surrounded by his family and loved ones.

"We deeply regret to inform you that the Honourable Jack Layton, leader of the New Democratic Party of Canada, passed away at 4:45 am today, Monday August 22. He passed away peacefully at his home surrounded by family and loved ones. Details of Mr. Layton’s funeral arrangements will be forthcoming," said a statement from Layton's wife, Olivia Chow, a fellow NDP MP, and Layton's children Michael and Sarah.

Fighting with hope and optimism was a recurring theme in Layton's life. Long before his battles with cancer, Layton had developed a reputation as a fighter — a determined, goal-oriented, passionate one who would take on a cause and not let go.

In his teens in the 1960s, he led a fruitless bid to have a youth centre built in his hometown of Hudson, Que. Later, as a community organizer and activist in Toronto, and then in his political work, Layton showed a passion for such issues as the environment, AIDS, poverty, violence against women, public transportation and homelessness.

That last area of interest led him to write a book, Homelessness: The Making and Unmaking of a Crisis, which was published in 2000. He was also the author of Speaking Out: Ideas That Work for Canadians (2004).

Layton also fought for aboriginal issues, and was given credit by Prime Minister Stephen Harper in 2008 for his role in shaping the federal government's apology for the residential school system.

As longtime New Democrat and union leader Al Cerilli told CBC News in an interview several years ago, "Good or bad, he's on the front page, he's in your face," he said. "Jack is not shy, he is of that nature, of bringing the things out and putting them on the front page."

Politics in the family

Born in Montreal on July 18, 1950, Layton had politics in his blood. His great-grand uncle William Steeves was a Father of Confederation.

His great-grandfather Philip Layton came to Canada from Britain as a blind teenager and helped pressure the federal government to bring in a $25-a-month pension for the blind.

His grandfather Gilbert Layton was a Quebec cabinet minister under Maurice Duplessis and his father Robert Layton was a Tory cabinet minister in Brian Mulroney's Conservative government.

That family tradition lives on. Layton's son Michael followed in his father's footsteps as a Toronto city councillor.

In addition to learning about politics first-hand from his family, Layton studied political science and economics at McGill University, graduating in 1970. He went on to earn a master's degree and his PhD in political science at York University in 1983. He wasted no time putting his knowledge from the classroom into practice and ran for Toronto city council in 1982 before he had even finished his doctorate.

Layton didn't leave the classroom after winning his seat on city council. While making waves at city hall, he taught politics at the University of Toronto, York University and Ryerson.

Layton ran unsuccessfully for mayor in Toronto in 1991, and twice failed to win a seat in the House of Commons that decade. But he kept fighting.

Emergence on national scene

Layton's profile on the national scene was boosted by his election as president of the Federation of Canadian Municipalities in 2000, and three years later he made a run for the leadership of the New Democratic Party. He defeated several sitting NDP MPs in the heated race and in his victory speech, Layton talked about hope.

"Hope ... is what drives New Democrats," he said, adding that his party "will always be the party of hope."

He led the party for a year before he tried for a seat in the House of Commons, in the 2004 federal election, when he was finally victorious in the Toronto-Danforth riding. And in 2006, Layton's wife, Olivia Chow, joined him as the MP for the nearby Toronto riding of Trinity-Spadina.

Jack Layton watches federal election results in Toronto on May 2, 2011, with his wife, Toronto MP Olivia Chow, and his granddaughter Beatrice. Andrew Vaughan/Canadian Press Once again they were allies in an elected chamber. Layton and Chow had been city councillors together in Toronto and were married in 1988.

Olivia, his two children from a previous marriage (to Sally Halford), and his beloved granddaughter, were a great source of pride for Layton. He was quick to pull out his BlackBerry and show off photos of his daughter Sarah's baby, Beatrice. He looked forward to what he called his "Bea time."

Layton also made sure some of his time was devoted to exercise. A competitive swimmer in his youth, he maintained an active lifestyle and was dedicated to squeezing workouts into his hectic days. After his first cancer diagnosis, he adopted an even healthier diet, much to Olivia's satisfaction.

The couple had faced cancer together before — Chow had thyroid cancer in 2000. They weathered that rough patch, just as they had various controversies in their political lives.

Layton could poke fun

Some public figures have one defining characteristic, physical or otherwise; Layton had several. He was known, for example, to be an MP who would ride his bike to work.

He was of course also known for his moustache, and took it in good stride on April Fool's Day when reporters on the 2011 campaign sported paper ones to poke fun at him.

He could poke fun at himself too, and used his musical talents on occasion to do so. He was known for breaking out his guitar on campaign planes and passing around songbooks so everyone could join in.

At the annual press gallery dinner in 2005, Layton entertained the crowd with what he called the NDP's new theme song. The lyrics to the tune of King of the Road included, "Party for sale or rent, it's as close to power as I'll ever get."

Landmark victory in last election

Six years after joking about being far from power, Layton was handed the keys to Stornoway, the official residence of the opposition leader, after winning a record number of seats in the House of Commons for the NDP and knocking the Liberals out of second place in the spring election he helped trigger.

It was a landmark victory for Layton, one that had been years in the making, as the party's fortunes had steadily improved under Layton's leadership. In his first three elections, the NDP climbed from 18 to 37 seats. He surrounded himself with loyal staff who helped him change the way the NDP communicated and fundraised. And together they made an incredible breakthrough in Quebec, starting with a by-election win in 2007 and a landslide 59 seats in the May election.

"In rebuilding the party, and generating enthusiasm from coast to coast in the party.... And putting roots down that are underway in the province of Quebec ... these are major, major accomplishments," former NDP leader Ed Broadbent told CBC News in a recent interview. "And he's going to be remembered ... you know, up there with Tommy [Douglas], with the great leaders of our party and movement. Jack's there."

In his final public press conference, where he announced his repeat battle against cancer, Layton maintained his trademark optimism, saying he was hopeful the NDP would keep moving forward and replace the Conservative government.

Though he looked and sounded weak, Layton's resolve was strong. He wanted a better Canada and said his party would help build "the country of our hopes, of our dreams, of our optimism, our determination, our values and our love." Those were the last words Layton said publicly to Canadians, before a final, "Thank you very much."