Alexander, who died on Friday at the age of 90, was Canada's first black member of Parliament, first black cabinet minister, and served as Ontario's lieutenant governor from 1985 to 1991.
Ontario Premier Dalton McGuinty, Lieutenant-Governor David Onley and several members of Alexander's family, including his widow Marni, were at Queen's Park to remember Alexander and sign a book of condolences.
Jason Kipps, Alexander's stepson, remembered him as a "friendly guy" who was also a trail-blazing public figure.
"I think he made a significant contribution to this province and this country," Kipps said. "He was an inspiration for a lot of people and I think that will live on."
Alexander's casket sat in the legislature's main hallway, covered with some of the celebratory medals he had been awarded through his life.
His body was brought from Hamilton to Toronto early Sunday afternoon, where it will lie in state until Monday night.
His casket will then be transported back to Hamilton, where Alexander is scheduled to lie in repose at Hamilton city hall until a state funeral on Friday.
Born in Toronto in 1922 to West Indian immigrants, Alexander was a wireless operator with the Royal Canadian Air Force during the Second World War.
He became the first black member of Parliament when he was elected in 1968, and was re-elected three times, in 1972, 1979 and 1980.
Alexander became Canada's first black cabinet minister when he held the labour portfolio from 1979 to 1980 under the Progressive Conservative government of Joe Clark.
Samuel Getachew, who immigrated to Canada from Ethiopia the year Alexander became lieutenant governor, came to watch Sunday's procession and said Alexander showed young black men that great barriers could be overcome.
"His legacy is that he told us through his life that we could have a Canadian story, we can come from the poorest country as I have come from, but we can have a Canadian success story."
Ontario NDP leader and Hamilton Centre MPP Andrea Horwath said Alexander always remained loyal to his native Hamilton, even with his national successes.
"He's achieved these great things that we look up to in many ways because they're the highest of offices, but when push came to shove he was a Hamiltonian," she said on the steps of the legislature in Toronto.
"He loved our city, he loved our community and he put his name to a lot of causes and got involved in a lot of causes around the country, but also in Hamilton. He never forgot his hometown."
Ontario Minister of Consumer Services Margarett Best said Alexander not only motivated her personally by sharing encouraging words but also inspired people from all walks of life across the country.
"He achieved many firsts and all Canadians can be truly proud of Lincoln Alexander and the legacy that he leaves behind."
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