Richard C. Holbrooke, the Obama administration’s special representative for Afghanistan and Pakistan since 2009 and a diplomatic troubleshooter who worked for every Democratic president since the late 1960s and oversaw the negotiations that ended the war in Bosnia, died Monday evening in Washington. He was 69 and lived in Manhattan.

His death was confirmed by an Obama administration official.

Mr. Holbrooke was hospitalized on Friday afternoon after becoming ill while meeting with Secretary of State Hillary Rodham Clinton in her Washington office. Doctors found a tear to his aorta, and he underwent a 21-hour operation. Mr. Holbrooke had additional surgery on Sunday and remained in very critical condition until his death.

Mr. Holbrooke’s signal accomplishment in a distinguished career that involved diplomacy in Asia, Europe and the Middle East was his role as chief architect of the 1995 Dayton peace accords, which ended the war in Bosnia. It was a coup preceded and followed by his peacekeeping missions to the tinderbox of ethnic, religious and regional conflicts that was formerly Yugoslavia.

More recently, Mr. Holbrooke wrestled with the stunning complexity of Afghanistan and Pakistan: how to bring stability to the region while fighting a resurgent Taliban and coping with corrupt governments, rigged elections, fragile economies, a rampant narcotics trade, nuclear weapons in Pakistan, and the presence of Al Qaeda, and presumably Osama bin Laden, in the wild tribal borderlands.