People wave flags in the district of Umraniye in Istanbul on May 21 during an election rally of the leader of the pro-Kurdish Peoples' Democratic Party. (Bulent Kilic/AFP/Getty Images)

— The black stone citadel of this ancient walled city is now a tourist attraction, home to artisan kiosks and tea shops. But to Dilsah Ozgen, a 76-year-old widow, it remains a symbol of pain.

“There was a time if you got arrested and taken to the castle, you would never get out,” recounted Ozgen, who said her husband was detained and disappeared in 1997, during the most difficult years of the conflict between the Turkish state and Kurdish separatists. “They say there are thousands of bones still there.”

Today, the sole visible sign of political struggle flaps in the breeze along one tower: a giant banner showing the smiling faces of two leaders of the People’s Democratic Party, or HDP, and their slogan, “Yes to great humanity!”

Turkey will hold elections Sunday for the 550 seats in its Grand National Assembly, the country’s parliament. The vote will determine whether the governing Justice and Development Party — known as the AKP — will win enough of a mandate to be able to push through a new constitution and give President Recep Tayyip Erdogan unprecedented executive powers.

Erdogan’s main obstacle? The Kurds. If the HDP, a Kurdish-dominated party, wins at least 10 percent of the electorate — a minimum requirement for a party to enter parliament — it will command enough seats to check Erdogan’s ambitions, and enough clout to push its own agenda.

A HDP banner hangs on the side of the historic city walls of Diyarbakir. (Ishaan Tharoor/The Washington Post)

“This is the most important election I can remember,” said Reha Ruhavioglu, a local Kurdish activist. “We’ll see if it gets the Kurdish people somewhere.”

It’s a remarkable moment for the Kurds, who make up an estimated 15 million of Turkey’s nearly 80 million people. As many as 40,000 people have been killed in the war between Turkish forces and the banned Kurdistan Workers’ Party, or PKK, since it flared in the early 1980s.

These days, the fighting is at a low ebb. And the election campaign has been largely peaceful. But Friday, two explosions ripped through a huge rally of HDP supporters in Diyarbakir, killing two people and wounding more than 100. Officials said it wasn’t clear whether the blasts were caused by an accident or an assailant.

For much of the past century, Kurds endured widespread discrimination at the hands of a Turkish state that did not accept their distinct identity. They were officially recognized as “mountain Turks” and barred from even spelling their names with certain consonants not used in written Turkish. Now, their most popular political party is poised to become a key player in the capital.

Few doubt that the AKP will win the most votes Sunday, but there’s still a lot riding on the election. Since coming to power in 2002, ­Erdogan’s party has been credited with enacting significant economic reforms and subduing the country’s long-meddling military. But after the AKP’s long tenure, opposition to Erdogan and the party has grown particularly intense.

Liberals in the country’s wealthy western coastal cities worry about the party’s conservative, religious agenda corroding the secularism of politics in Turkey, which is an almost entirely Muslim country. Political opponents, rights groups and media watchdogs warn that Erdogan is becoming increasingly authoritarian, censoring the Internet and pressuring journalists and critics.

After serving the three four-year terms he was constitutionally allowed as prime minister, Erdogan was elected president in 2014. He is determined to transfer more authority to what is technically a ceremonial position — a change his supporters say would lead to better governance, but which critics argue will allow him to rule for many years to come.

“Erdogan has the mind-set of an Ottoman emperor,” said Metin Sumer, a 30-year-old resident of Diyarbakir and an HDP supporter.

The HDP’s charismatic young leader, Selahattin Demirtas, has vowed to stop Erdogan from making this move. Polls suggest a significant majority of Turks don’t want to see a presidential system replace the parliamentary structure, and the HDP is counting on non-Kurdish, anti-Erdogan votes to get it across the 10 percent barrier.

To that end, the HDP’s list of potential deputies is a veritable rainbow nation, boasting Kurds, Turks, Armenians, leftists, Christians, Muslims, Turkey’s first openly gay parliamentary candidate, and the highest proportion of women of any party.

“The fate of the Kurdish nationalist movement is now interlocked with the fate of liberal, democratic Turkey,” said Soner Cagaptay, a fellow at the Washington Institute for Near East Policy.

A charismatic leader

The surge of the HDP is thanks, in part, to the magnetism of Demirtas, a 42-year-old leftist lawyer with an easy smile and a penchant for jokes. He is a departure from the stereotypical lecturing, paternalistic Turkish politico.

In the 2014 presidential election, Demirtas won 9 percent of the vote. “That was a dry run for Demirtas,” said Bulent Aliriza of the Center for Strategic and International Studies in Washington. “And it turned out he was a great campaigner, one who appealed to the disaffected, to those wanting to take a tough stand against Erdogan.”

The irony is that, of all the parties in the Turkish establishment, the AKP has done the most for the Kurds in recent history. In 2005, Erdogan delivered a landmark speech in Diyarbakir, the largest city in Turkey’s predominantly Kurdish southeast, acknowledging the need to address the “Kurdish issue.” AKP reforms have slowly loosened the shackles once placed on Kurdish cultural identity.

“We couldn’t listen to Kurdish music. We couldn’t even speak our language without getting into trouble,” said Somet Akduman, a 55-year-old advertising executive in Diyarbakir who says he will vote for the AKP. “Everything has changed, thanks to them.”

While the AKP seeks to counter the HDP’s new influence on the wider Turkish stage, it has seen its backing among Kurds weaken. Some point to Turkey’s lack of support for Kurdish militias fighting the Islamic State in neighboring Syria, where many Turkish Kurds have ancestral and familial ties.

Others point to a speech in March in which Erdogan dismissed the notion of a “Kurdish problem,” backtracking on his remarks a decade earlier. His rhetoric was seen as pandering to far-right nationalist Turks, and it incensed Kurds who still seek a resolution to a long-stalled peace process with the PKK, amnesty for militants and inquiries into ­abuses during Turkey’s decades of counterinsurgency.

The PKK is considered a terrorist organization by Washington and Ankara, but it seems almost every household in Diyarbakir can point to some connection to the nationalist guerrilla movement. Demirtas himself is believed to have a brother “in the mountains.”

“You cannot divide between PKK sympathizers and HDP voters,” said Ziya Pir, a leading HDP candidate from Diyarbakir and nephew of a former PKK leader.

The PKK no longer clamors for independence, instead seeking more autonomy for the Kurds. The HDP wants a federal system that further decentralizes authority to Turkey’s regions.

“We want peace,” Pir said. “We want a new constitution with freedoms for all individuals, where all cultures and religions can find themselves equally.”

Most HDP and AKP supporters in Diyarbakir are convinced the Kurdish party will receive the votes it needs to enter parliament. But there are fears of what may come to pass if they don’t, with rumors swirling over potential election fraud.

“If we don’t reach the threshold, then everything will be finished,” said Ibrahim Ataman, a 50-year-old man wearing a traditional Kurdish headscarf. Near the sunny corner where he sat drinking tea, a truck in HDP colors blared PKK guerrilla anthems.

For Ozgen, the widow, the vote is part of a longer struggle for dignity. She said her husband was seized by police years ago as part of a larger operation to find their son, a prominent guerrilla fighter. She now works with a group of bereaved women in Diyarbakir who lost children in the conflict.

“I believe the HDP will get 10 percent of the vote,” she said. “And with that victory we will go to parliament and put our hands on Erdogan’s throat.”

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