Jailed Kurdish rebel leader Abdullah Ocalan has ordered his fighters to cease fire and withdraw from Turkish soil as a step to ending a conflict that has killed 40,000 people, riven the country and battered its economy.
Hundreds of thousands of Kurds, gathered in the regional centre of Diyarbakir, cheered and waved banners bearing Mr Ocalan's moustachioed image when a letter from the rebel leader, held since 1999 on a prison island in the Marmara Sea, was read out by a pro-Kurdish politician.
"Let guns be silenced and politics dominate," he said to a sea of red-yellow-green Kurdish flags. "The stage has been reached where our armed forces should withdraw beyond the borders ... It's not the end. It's the start of a new era."
Prime minister Tayyip Erdogan has taken considerable risks since he was elected in 2002, breaking taboos deeply rooted in a conservative establishment, not least in the military, by extending cultural and language rights to Kurds.
He must now carry a sceptical conservative establishment with him, just as Mr Ocalan from his prison island must marshal and keep the obedience of fighters in the hills of northern Iraq. The road must be a rough one with suspicions on both sides.
"The language is the language of peace, we need to see it implemented," interior minister Muammer Guler said, condemning the absence of red Turkish flags at the celebrations.
Rebel fighters would withdraw to their bases in the mountains of northern Iraq, which they have used as a springboard for attacks on Turkish soil. The Turkish air force has frequently attacked the strongholds.
Ocalan's Kurdistan Workers Party (PKK), regarded by the United States, European Union and Turkey as a terrorist group, launched its campaign in 1984, demanding an independent Kurdish state in the southeast of Turkey. It has since moderated its demands to political autonomy and broader cultural rights in an area where the Kurdish language was long formally banned.
"There is a strategic shift happening," said Ertugrul Kurkcu, a parliamentarian from the pro-Kurdish BDP party. "The Kurdish liberation movement is moving from an armed campaign to a cultural one. And the PKK accepts this."
Mr Ocalan, isolated from his fighters for over a decade, has won public backing for a truce from field commanders over the last week; but there have been signs of scepticism in their ranks. Last month, at a meeting with Kurdish politicians he accused them of unwarranted pessimism over peace talks.
"I'm angry with them," Mr Ocalan said, voicing opposition to their "war system", or strategy.
There are still dangers of division over the terms of any deal or between the PKK figures negotiating it.
The live broadcast on national television of the scenes in Diyarbakir would have been unthinkable even a few months ago. Throughout the conflict, insignia of the outlawed PKK has been strictly banned. A huge bonfire was lit as Kurdish "Newroz" new year celebrations began, a soundtrack of Mr Ocalan's past speeches playing over loudspeakers.
A settlement would lift a huge burden off Turkey, though it would be viewed with deep suspicion by hardline nationalists who fear Kurds would resume a drive for independence.
"The PKK is challenging the state and this is a display of power by them," said Ozcan Yeniceri, a parliamentarian from the MHP, Turkey's main nationalist opposition party.
"In place of a Turkish Republic, the road is being paved for formation of a federal independent Kurdish state."
The war has drained state coffers, stunted development of the mainly Kurdish southeast and scarred the country's human rights record. A peace would bolster the NATO member's credibility as it seeks to extend influence across the Middle East, and remove a stumbling block from its path to join the EU.