Boom, then bust: A glittering career ended in failure
He had been marked for success early. Born in 1951 the son of a Church of Scotland minister, Mr Brown was fast-tracked into Edinburgh University aged just 16, and while working as a politics lecturer and journalist, fought his way into a prominent position in the Scottish Labour Party, arriving at Westminster in 1983 as MP for Dunfermline East.
He joined the front benches within two years, rising to shadow chancellor in 1992. After the sudden death of John Smith in 1994, he was viewed by many as a natural successor, but the infamous deal with Tony Blair that saw the younger man take the leadership with a promise to hand it over after a period saw him triumph in 1997 at the head of the New Labour project of which Mr Brown was a key architect.
Mr Blair's victory sparked a bitter feud between the two that simmered for years and was claimed to have undermined the effectiveness of the administration, with Mr Brown demanding a date for a handover of power. Meanwhile, he earned the reputation as the "Iron Chancellor" over a decade, claiming to have ended boom and bust.
He got his wish to become Prime Minister on June 27 2007 when Mr Blair stepped down, but his reputation for decisiveness soon began to unravel, dumping the idea of a snap election amid unfavourable opinion polls.
And then storm clouds gathering over the economy called into question his stewardship of the Treasury. Opponents revived the claim by an anonymous Labour insider that Brown was "psychologically flawed".
Yet he led international agreement at the London summit to tackle the downturn and cemented a surprising new alliance with former enemy Peter Mandelson to see off a series of leadership challenges.
While Mr Brown was capable of acts of great generosity and kindness in private, his time in office was tainted by a perception even among his own ranks that the simmering ambition he had brooded over for so long had rendered normal relationships all but impossible with many of his colleagues.