Cramped in a tarpaulin tent with his family of nine, Ali Mahmud remembers his spacious ancestral home in the northern Iraqi town of Bashiqa he last set foot in more than two years ago.

"It was built long ago by my great grandfather," the construction worker, 50, told AFP.

But in August 2014 they fled in terror along with other members of their Yazidi community when Islamic State jihadists swept through the region, unleashing a campaign of murder and kidnappings against them that the United Nations called a genocide.

Now Ali and his family are among the tens of thousands of Yazidis scattered around camps for their displaced community in Kurdish-controlled territory.

They are dreaming of returning home as Kurdish and Iraqi forces push IS from their lands in an offensive to oust the group from Mosul, the last major population centre it controls in the country.

"They did a lot of bad things to the Yazidi community and especially to the women, they took them as slaves," Mahmud's sister-in-law, Solaf Hossein, said.

"We used to live well, in a peaceful way and we don't know why they have been targeting us."

The Yazidis are neither Muslims nor Arabs and follow a unique faith despised by IS.

The Kurdish-speaking minority -- mostly based around Sinjar mountain in northern Iraq -- has kept its culture and religion despite earlier persecution by more dominant groups around them.

But a new chapter of horror came when IS arrived, massacring Yazidis in Sinjar, forcing tens of thousands of them to flee, and capturing thousands of girls and women as spoils of war to be used as sex slaves.

A report from the UN in June said the group "sought to erase the Yazidis through killings, sexual slavery, enslavement, torture and inhuman and degrading treatment".

- 'Long to go back' -

In terms of the tragedy inflicted on their community, the Mahmud family can almost be considered lucky.

They managed to clear out of their town with their relatives before the jihadists arrived.

But they are still now members of an uprooted people and say they are struggling to maintain their centuries-old culture that IS sought to eradicate.

"Here it's not like before, we used to have our temple and be able to pray," Hossein said.

"We are missing everything... our temples and events, we are missing everything, all of our costumes and traditions, since we fled, even the costumes and traditions become flavourless."

Last week Kurdish forces retook the family's hometown of Bashiqa and for the first time since they left they glimpsed their home -- filmed on a mobile phone by a Yazidi fighter involved in the offensive.

It is still standing, but strewn with rubble and wreckage that will take a lot of work to put right.

"We long to go back, if only for an hour -- that would be enough," Hossein says.

But that will likely take some time as Iraqi forces are only slowly pushing the jihadists back in Mosul and the Yazidis are wary about returning until the threat from IS has been extinguished for good.

And even when they do return, dragging their community out of the ashes left by IS will likely prove a near impossible task.

"It won't get back as it used to be," Hossein said.

"But hand in hand the Yazidis will continue to rebuild the community again and God willing through cooperation it will come back."