Once rebel foreign minister Zaini Abdullah won 55.8 percent of the vote in last week's election beating former governor Irwandi Yusuf, according to results announced by the Aceh independent election commission.
Indonesia's westernmost province, oil and gas rich, was devastated by a tsunami in 2004 that left 170,000 dead or missing. The disaster prompted the end of a three-decade insurgency in which thousands were killed and human rights abuses soared.
Around 13 people died in the run-up to the election, according to Concord Consulting group, a risk firm based in Jakarta. There were also allegations of voter intimidation.
Even so, Aceh's second election forms part of a transition away from violence, according to analysts.
"Aceh has been so far an overwhelmingly successful example of resolving a guerilla conflict through allowing the rebels to take part in the political process," said security analyst Sidney Jones of the Brussels-based International Crisis Group.
Myanmar sent a delegation to Aceh last year to study its example of conflict resolution, an Indonesian foreign ministry official said.
Aceh is the only Indonesian province that has sharia law, though the subject played little role in the election. Abdullah said sharia must be applied more evenly.
"On the bylaw about cutting the hands for stealing, you can cut two, three, twenty, thirty hands, but that will not resolve the problem. There should be a preventive action as well through education," Abdullah, 71, told Reuters.
Abdullah worked as a doctor from 1972-1976 before joining the Free Aceh Movement (GAM) and fighting for four years in the rebellion. He later sought asylum in Sweden where he represented the movement as foreign minister before returning in 2006.
