Friends, colleagues and rivals spoke of his principled politics and his rare wit as well as their deep sadness at his death.
The former Ross, Skye and Lochaber MP, who leaves a ten-year-old son, Donald, was found dead at his cottage in Fort William on Monday night.
Prime Minister David Cameron said his death was an “absolute tragedy”.
“It is not that often in politics that someone comes along with brains, talent, wit and bags of humanity, and Charles had all of those things,” Mr Cameron said. “He achieved so much so young and he has been taken from us too soon.”
Although the official cause of the former Lib Dem leader’s death will not be known until the results of a post-mortem examination, Mr Kennedy had a history of problems with alcohol and friends said he had been drinking in the days before he died.
The outgoing Lib Dem leader Nick Clegg said that on a good day, Mr Kennedy had “more political talent in his little finger than the rest of us put together”.
Mr Clegg added: “Charles’s untimely death robs Britain of one of the most gifted politicians of his generation. Charles devoted his life to public service, yet he had an unusual gift for speaking about politics with humour and humility which touched people well beyond the world of politics.”
First Minister Nicola Sturgeon said: “Charles Kennedy was one of these rare people in politics. He was an incredibly talented, gifted, effective politician – I think one of the most talented politicians of his generation.
“And yet somehow he also managed to be universally liked across the political spectrum and indeed across wider society.”
A statement from the Kennedy family said: “It is with great sadness, and an enormous sense of shock, that we announce the death of Charles Kennedy.
“We are obviously devastated at the loss. Charles was a fine man, a talented politician, and a loving father to his young son.”
Senior Lib Dem sources said it was thought that Mr Kennedy had suffered a heart attack before his body was found in his home by his partner, Carole MacDonald.
Mrs MacDonald, the widow of Mr Kennedy’s lifelong friend Murdo MacDonald, had been the politician’s companion following the breakdown of his marriage, although they had kept their relationship low key.
She found him on Monday evening and alerted the ambulance service. They contacted police, who attended Mr Kennedy’s home in Fort William.
His death came barely three weeks after he lost his seat, and friends were concerned about how his health would stand up to the blow. The general election had been very difficult for him as he had lost his father Ian just before the campaign began.
Mr Kennedy Snr’s death on top of that of his mother Mary, in 2013, had hit him hard. Furthermore, his brother, also Ian, had health problems which had confined him to a wheelchair.
“I was worried that Charles would go to pieces when his father died,” one senior Lib Dem said. His friends, however, were encouraged when the politician gave a brilliant eulogy at his father’s funeral, held in St John’s Parish Church, the Roman Catholic church in Caol where the family had always worshipped.
Mr Kennedy spoke movingly about his parents, saying that he was unable to think about his father without thinking about his mother.
He spoke of their love of music – his father was a renowned Highland fiddler and his mother the church organist.
His father’s talents as a violinist were recalled as Mr Kennedy told how he would play in village halls when he himself was campaigning in the 1983 general election.
“The voters never came to listen to me. They came to listen to my dad,” Mr Kennedy quipped.
But given his well-publicised alcohol problems, there were concerns about how he would cope with what was turning out to be a difficult general election campaign. Although his father’s death badly affected him, Mr Kennedy managed to get back out campaigning – a task for which his good humour and wit made him ideally suited.
But even a politician of his qualities found the campaign trail hard going. In public he put on a brave face but in private admitted his seat was in danger.
Lib Dem strategists felt that he had a good chance of hanging on through the force of his personality and being such a popular figure in the seat which he had held for 32 years, ever since he had been elected as the “Baby of the House” aged just 23.
But on the night of the count, as the boxes came in from the west, it became clear that Mr Kennedy would become yet another Lib Dem casualty. Shortly after his defeat, he was seen in London where, again, he was said to be in good spirits.
In the meantime, Willie Rennie, the Scottish Lib Dem leader, had been in touch, suggesting that he make a new political career in the Scottish Parliament. It was an offer Mr Kennedy was willing to consider.
The veteran Liberal Democrat Baroness Williams said that he had become “difficult to reach”.
“He didn’t want to be tracked down. I think he moved into a more and more lonely position,” she said. “Not because he hadn’t got friends, but because he wasn’t sure that he wanted to bring the friends into his life to help.”