JALAWLA, Iraq — Behind Iraq’s front lines against the so-called Islamic State, Kurdish and Shia factions already are drawing a blueprint for what could be the region’s next major conflict.

In the city of Jalawla in Iraq’s Diyala province, near the Iranian border approximately 80 miles east of Baghdad, Kurdish forces have given the boot to the Shia militia they previously allied with to take the city from ISIS in a bloody November battle. Last month, the commanding Kurdish Peshmerga general in Jalawla threatened to start shooting if the Shia refused to leave the city immediately.

“This area is ours now, and that’s not changing,” Brigadier General Mahmoud Sangawi told The Daily Beast. He added that Jalawla, an abandoned city that previously had 83,000 people and was 80 percent Sunni Arab in 2003, would soon have a Kurdish mayor. Sangawi bragged that henceforth the city would also be called by its new Kurdish moniker, “Golala.”

Not so fast, say the Shia militias. They were recruited in the name of a fatwa from Iraqi Grand Ayatollah Ali al-Sistani in June 2014, after the Iraqi army’s humiliating loss of Mosul, Iraq’s second-largest city, virtually without a fight. Many are trained and advised by Iranians, and they have been the spearhead of Baghdad’s efforts to recover lost territory in the name of the national government.

The Kurds, meanwhile, have fought hard to protect, consolidate and indeed expand areas they consider “their” territory.

“They [the Kurds] need to recognize this region is Iraq,” says Ali Khorasani, the commander of the Hashd al-Shaabi militias that Sangawi’s Peshmerga expelled from Jalawla. Hashd al-Shaabi is the Arabic term for Popular Mobilization Units, the name preferred by the volunteer Shia militias.

Khorasani said the Kurds “are strong, and they’re very organized, and our relationship was good, but now our relationship has problems.” And that appears to be an understatement. When asked if Kurdish moves in the region might lead to another war, Khorasani replied tersely: “Maybe.”

For now, Khorasani’s unit has been dispersed to the south of Jalawla around a town called Sadiya. It’s only a five-minute drive from Jalawla, but Kurdish forces are limiting access to Sadiya and prevented us from going there. Khorasani spoke to The Daily Beast by phone.

The ISIS blitz of northern and central Iraq one year ago sent the on-paper highly trained and well-equipped Iraqi army scrambling, and led to the sacking of controversial Shia Prime Minister Nouri al-Maliki. He was widely criticized for his sectarian policies that alienated the country’s Sunni Arabs, who are now the main support base for ISIS.

The Iraqi army’s retreat also opened the door for Kurdish forces to seize large swaths of territory abandoned by government forces.

Now, the central government’s inability to deal decisively with ISIS in Anbar province and its loss of the Anbar provincial capital, Ramadi, has seen the Kurds acting even more brazenly in anticipation of an independence push. Iraqi Kurdistan President Masoud Barzani has promised a long-awaited Kurdish independence referendum.

“Certainly an independent Kurdistan is coming,” Barzani said on a visit to Washington, D.C., on May 6. “It will take place when the security situation is better and when the fight against ISIS is over.”

“We could see outright civil war,” Farhan Siddiqi, a research fellow on international politics and national security at the Middle East Research Institute (MERI), tells The Daily Beast. Siddiqi says he believes the Kurds and the Shia central government would face domestic and international pressure to avoid such a conflict, but if cooler heads failed a hypothetical conflict could escalate into something even worse than the current ISIS war.

Since the summer of 2014, the Kurds have increased their territory by 40 percent, most notably around the oil-rich city of Kirkuk, often called the “Kurdish Jerusalem.” Today, Kirkuk has a Kurdish population of around 50 percent, along with large groups of Arabs and Turkmens. The city and its outlying territories were frequent targets of “Arabization” by the Saddam Hussein regime, a policy meant to shift the ethnic balance of power there as he waged a genocidal war against the rebellious Kurds. Now they want the city back, but Arab families who have lived there for decades have no place to go.

Areas like Jalawla are a different matter. It is closer to Baghdad than to the Iraqi Kurdish capital, Erbil. It, too, was the target of waves of Arabization, but it has been a majority Arab city for decades. By Sangawi’s own admission the population was less than 10 percent Kurdish in 2003.

“The Baath regime had a process of oppressing the Kurdish people. They had to change their names to Arab names or leave the city,” Sangawi says. “When filling out forms they had to register as Arab. In 1970, 32 percent of this city was Kurdish. The city was only 8 percent Kurdish at the time of the American invasion in 2003. The Arabs tried to rob the Kurds of their land.”

Today, Jalawla has been abandoned by its civilian inhabitants, many of whom supported ISIS, according to Sangawi. Feral dogs dart in front of Peshmerga convoys and Kurdish graffiti proclaims the city part of Kurdistan. The immediate surrounding area of the town—dusty, flat fields speckled with palm groves—clashes with the green, mountainous terrain often associated with Kurdistan, and syncs up more with stereotypically Arab lands.

Parts of Jalawla, especially the former ISIS command center on high ground overlooking the city, have been reduced to rubble. However, a spring bloom of un-manicured pink desert roses has overrun the walls and sidewalks, offsetting the many bullet holes and craters that otherwise dot the settlement.

“One hundred and ten Peshmerga died in the fighting. When ISIS came in here they left many IEDs and explosives on the roads,” says Sangawi.

But the November fighting wasn’t the area’s first battle, and likely not its last. The Kurdish-Arab rift in the city goes back over a millennium.

Golala, Jalawla’s Kurdish name, means the “land of flowers.” Its Arabic title’s etymology is more grisly. In 637 AD, Arab Muslim forces during the early Islamic conquest of the Middle East won a decisive battle here against a Zoroastrian Persian force. A popular tale in the region holds the Arabs named the location Jalawla from an Arabic verb meaning to cover or to fill, as so many Zoroastrian corpses filled the landscape.

Sangawi knows this tale, and says he considers the Zoroastrians the Kurds’ forebears before Arabs took their territory—a perfect and historically convenient parable for Kurdish claims on the region.

Dark-haired with a round face, thick droopy mustache and rosy cheeks, the 63-year-old Sangawi at first comes across as a friendly, grandfatherly type, albeit one who travels with an entourage equipped with RPGs and machine guns. And most grandfathers don’t blithely threaten former heads of state.

“We’ve killed lots of people, a lot of them like Maliki,” he says of the former Iraqi prime minister, who said in a TV interview last month that anyone wishing to break up Iraq would create a “river of blood.”

“Maliki can eat shit,” Sangawi chuckles.

Sangawi’s been with the Peshmerga since the 1970s and has jumped around the Kurds’ various political parties, at one point even becoming a Marxist before joining up with the Patriotic Union of Kurdistan (PUK), the party of former Iraqi President Jalal Talabani.

Compared to Sangawi’s stance of bold antagonism, Khorasani is more conciliatory. The 45-year-old says he was in the legal profession before volunteering for the militia, and he makes a point of saying how the liberation of Jalawla was a joint effort. Even before then, he adds, the Kurds and Shia Arabs could find common cause.

“This is Iraq. We used to be united. They opposed the former regime and so did we,” he laments. “We were one.”

But Sangawi counters: “We were both against Saddam Hussein. We fought together. However, when the Shias came to power they treated us the same as Saddam Hussein—that’s why we don’t have a good relationship now.”

Siddiqi, at the Middle East Research Institute, says the new Baghdad government under Prime Minister Haider al-Abadi has shown a willingness to negotiate and be more accommodating to Iraq’s minorities, but the country’s age-old tensions still run deep.

“Saddam Hussein is gone, but his authoritarianism still survives along all levels of Iraqi society,” Siddiqi says. “It remains to be seen if the government becoming more accommodating will reduce calls for independence.”

If a conflict were to occur, he adds, the Hashd al-Shaabi would be at the forefront of any government pushback against the Kurds. “The central government could easily call on the Shia militias it’s currently using against ISIS, using religious pretexts and slogans to drive them forward,” he says.

The central Iraqi government has already come under fire for its use of the militias, whose religious zealotry exacerbates sectarian tensions in Iraq. The government’s operation to retake the Sunni-majority Ramadi was originally named “At Your Service, Hussein,” in honor of a major Shia historical and religious figure. Human Rights Watch has also raised concerns that the Hashd al-Shaabi have committed serious human rights abuses while ostensibly fighting ISIS.

Siddiqi says the international community, including the central government’s main ally, Iran, would be wary of seeing another war in the region. “Iran wants peace, it does not want Iraq to become another Syria or another Yemen,” he says, adding that although opposed on many issues, the U.S. and Iran have tacit tactical cooperation in Iraq these days, and neither would support a Shia-Kurd conflict.

If a fight did occur, Siddiqi says he believes world powers would do their best to take a “hands-off” approach to avoid further escalation. If Kurdish independence were to succeed, he continues, it would only be accomplished via an agreement with Baghdad, not another war.

But far from Tehran and the Beltway, on the dusty plains of disputed Jalawla, Sangawi says he’s ready for that war, drawing little distinction between Shia Hashd al-Shaabi and Sunni ISIS, and viewing them both as his people’s ancient enemies.

“The Shia militias believe if they kill ISIS they’re going to heaven, and ISIS believes if they kill the Shia people they are going to go to heaven,” Sangawi declares. “They fight over religion, not for land.”

“For me, if they attack me I will attack them, because this is my land. If they come to this land, of course I will fight them.”