Mr Prince is a lawyer by training
Charles O Prince III resigned on Sunday as chairman and chief executive of one of the world's biggest banks: Citigroup.
"It is my judgment that given the size of the recent losses in our mortgage-backed securities business, the only honourable course for me to take as chief executive officer is to step down," he said in a statement.
It brings to an end almost 30 years of his involvement with companies that are now part of Citigroup.
Mr Prince received his law degree in 1975 from the University of South Carolina and took his first job as a lawyer for US Steel Corp.
He joined Commercial Credit Co in 1979.
That bank went through a series of mergers and acquisitions before merging with Citicorp in 1998.
Mr Prince rose to be chairman and chief executive of Citi's markets and banking division by 2002.
In October 2003, Sanford Weill, who had been responsible for the acquisition-spree that created Citi as the world's biggest banking group, was replaced by Mr Prince as chief executive.
He had been a fine deputy to Mr Weill, even postponing a kidney-cancer operation until the takeover of Salomon Brothers had been completed, according to Mr Weill's biographer.
Citibank founded in 1812
Group has 200 million customer accounts
Owns brands such as Diners Club and Schroder & Co
More than 300,000 staff worldwide
Owns $55bn of sub-prime debt
Mr Prince took on the job of chairman as well three years later.
Since October 2003, Citigroup's shares have fallen by about 20%.
Mr Prince was criticised by some shareholders from the start for his so-called umbrella model of corporate organisation.
The model involved having several separate lines of business overseen by a central management board.
Then in July he declared that Citigroup was "still dancing" in the private equity business that was about to be brought to a standstill by the credit crunch.
Mr Prince is 57 years old and married to Margaret Wolff, who is also a lawyer. He has two children from a previous marriage.
His replacement as chairman is Robert Rubin, who was US Treasury Secretary in the Clinton administration and also a former co-chair of Goldman Sachs.
The interim chief executive at Citigroup is Sir Win Bischoff, who was chairman of Citi Europe, having been head of the London-based merchant bank Schroders when its investment banking business was bought out in 2000 by Citigroup.