"He brought to the job intelligence, integrity, energy, a clear and practical sense of direction and an unwavering commitment to what he believed to be the wider public interest," Harper said at a public memorial for the former Alberta premier at Calgary's Jubilee Auditorium.
"Every place and every era have their leaders. They are confronted with the challenges of the events of the times in which they live. More often than not, these define them," Harper continued.
"However, a leader sometimes defines his own age and Peter Lougheed was that kind of leader."
Harper was among 2,400 dignitaries and citizens from across Canada who came to bid a final goodbye to Lougheed.
Lougheed, premier of Alberta from 1971 to 1985, died last week in hospital of natural causes. He was 84.
With Lougheed's wife, Jeanne, and four children looking on, Harper recalled Lougheed's epic battles with the federal government over oil resources in the 1970s and '80s.
"His motives (outside Alberta) were often questioned, his patriotism frequently attacked," said Harper. "But Peter Lougheed did not shrink from that fight. He embraced it.
"Peter Lougheed was always a proud Albertan and a fierce Canadian, understanding clearly that one part of Canada cannot succeed at the expense of another because our destiny is sown together in the fabric of this great nation."
Alberta Premier Alison Redford recalled the man she called a personal mentor and the transformative "architect of the province we all call home.
"Every single one of us woke up this morning in Peter's Lougheed's Alberta," said Redford.
"It was the Alberta of which he dreamed and it was the dream that he was able to make real."
Redford said that when she won the party leadership race last fall and became premier, Lougheed called her with congratulations.
"Before offering any advice (he) said five simple words: 'You are now my leader.' That gesture was truly humbling ... and it was one that I will remember for all of my life."
Another politician remembered Lougheed calling him at a less positive time in his political career. Jean Charest was one of only two federal Tories to keep their seats in the 1993 election.
"Where he was very significant for me in my life was when I became leader of the federal Progressive Conservative Party after the debacle of 1993 and asked for his advice," said Charest, who was premier of Quebec until his defeat in this month's election there.
"He helped us out with some of the policy conferences," he said outside after the service. "Here was this giant of a leader who was respected throughout the country giving his time."
Stephen Lougheed, Lougheed's oldest son, told the mourners that he would always recall a devoted and doting father who would spend hours throwing a ball for his kids and grandchildren, and would go to football and baseball games.
"My dad was always a team player. And the team that he was most proud of was his home team — his family, starting with mom," said Stephen.
"I can tell you we will all miss him tremendously."
The family held a private funeral service for Lougheed on Thursday.
Humorist and commentator Rex Murphy was the first to speak, evoking applause when he called Lougheed "the greatest premier that this country has ever seen."
He even brought a little levity.
"When other public men die we have to lie about them," he said.
"(But) this man is such an assembly of obvious salient virtues, and he conducted a life of such superb decorum and dignity, that it truly is us that are receiving the tribute that he was here a mere three years less than Lincoln's famous four score and seven."
Among those in attendance were former prime minister Joe Clark, Saskatchewan Premier Brad Wall and former Saskatchewan premiers Roy Romanow and Grant Devine.
Outside the auditorium, Clark said Lougheed's greatest talent was his ability to build coalitions and bridge differences.
"I think he always thought, 'What's the point of getting mad at people? Why do we drive them away when we can draw them in?'" said Clark.
Among the members of the public who lined up early to get one of the few seats available, Pat Allen was the first person in line.
"I'm here today to show my respects for this wonderful man," she said.
Allen said she met Lougheed in 1979 and had an apartment at Calgary's Elbow Towers, where Lougheed had an office.
"He was the most incredible man. I believe there were 130 of us living there. He knew every one of us by our first names. He was the kindest, most caring, friendly, honest politician I have ever met."
The memorial capped a week of tributes.
Earlier this week, hundreds filed past Lougheed's coffin as it lay in state in the marble rotunda of the legislature in Edmonton.
Thousands have delivered condolences and best wishes to the family online or in books placed across the province
Lougheed, born in Calgary and trained as a lawyer, is credited with creating a modern Alberta by using its oil resources to diversify the economy. He supported development of oilsands technology that now delivers billions of dollars to the province's coffers.
He became a provincial folk hero for battling federal encroachments on Alberta's oil wealth.
He cultivated culture and art and expanded recreational areas.
As a politician, he led a fledgling Progressive Conservative party to its first majority government, in 1971. The PCs have held power ever since, with Lougheed being succeeded by Don Getty, Ralph Klein, Ed Stelmach, and now Redford.
In retirement, Lougheed continued to advise politicians, including Redford and Harper, and spoke out on public policy issues.
The number of awards and commendations have been staggering. There are buildings, parks, scholarships and streets named in his honour. He was named to the Order of Canada in 1987 and the Alberta Order of Excellence in 1989.
This summer, the Institute for Research and Public Policy named him Canada's best premier in the last 40 years.
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