David Trimble

Trimble, elected Ulster Unionist leader in 1995 as a hardliner, became the unionist who signed. He took his party into the 1998 agreement despite half his MPs opposing it, won its referendum campaign and became First Minister, sharing the Nobel Peace Prize with John Hume. Repeated crises over IRA decommissioning eroded his support, and the Democratic Unionists overtook his party in 2003. His courage cost him his party's dominance, a pattern common among peacemakers.