The newly appointed governor of Anbar province, Souhaib al-Ani, told the recruits that it was the start of the liberation of the province, an estimated 65 percent of which has been under control of the Islamic State for the last year and a half.
"Today is not like any other day, today is the beginning of the end for those who have wreaked havoc on our homes," al-Ani told the recruits arrayed before him under the hot sun before an audience of military and tribal leaders.
"This is not like any other day because all of Iraq stands with you," he added, speaking at the ceremony in the town of Amiriyat Fallujah, a few kilometers (miles) south of the main IS-stronghold in Anbar, the city of Falluja.
Anbar's Sunni tribes were key to defeating al-Qaida in 2006 but afterwards, the Shiite-dominated government of Prime Minister Nouri al-Maliki cut funding to these Sunni forces. Many were later targeted and killed when the Islamic State swept into the province.
Repeated requests by tribal leaders for funds and arms were ignored, in part because the government distrusted the Sunnis, claiming many sympathized with the Islamic State.
In contrast, the state has invested heavily in Shiite militias, known as Popular Mobilization Units, which have played a major role in fighting the Islamic State around Baghdad and in other provinces.
Iraq's new Prime Minister, Haider al-Abadi, has been more open to arming the Sunnis and authorized the creation of a 6,000-strong Popular Mobilization Unit in Anbar.
Friday's recruits are all from the Albu Eissa tribe based in the town of Amiriyat al-Fallujah, which for the past year has been battling Islamic State forces based in their stronghold of Fallujah, just 30 kilometers to the north.
Sheikh Rajeh Barakat, a tribal leader and member of the Anbar provincial council said in the beginning some Sunnis supported the Islamic State, because of their anger at Maliki's government, but most did not and were now eager to fight the well-armed extremists.
"Once they realized the government really wanted to do something about the Islamic State, they started volunteering," he explained, predicting that many more Sunnis would join this militia to help drive the IS out.
Iraq's Sunnis are also sensitive about demands by Shiite militias, many of which are Iranian-backed, to participate in the fight against the Islamic State in Anbar — something critics say could severely alienate the Sunnis.
Qais al-Ghazali, the head of the Asaib Ahl al-Haq, said last week that his Shiite militia was ready to help in the fight in Anbar even though the prime minister and the United States opposed it.
Barakat said that the tribes didn't need the help of the Shiite militias, which many Sunnis have accused of carrying out atrocities against civilians during their operations.
"If we receive the same type of weapons as the southern Popular Mobilization Units, we can do the job on our own," he said, referring to the Shiite militias, which hail from the predominantly Shiite south. "We find it bizarre to see the kinds of weapons they get compared to the light weapons we get."
The new recruits will be given a 10-day training course before joining the fight, said the governor, in light of their long experience fighting already.
All new recruits will be vetted by a committee including a top military general, the deputy head of the Popular Mobilization Units and the Anbar governor himself.
The main fight against the Islamic State will likely still be carried out by elite army units, but the militias will be playing an important role in holding territory taken back from the Islamic State.
One of the main goals of any fight will be Fallujah, a stronghold of al-Qaida 10 years ago and one of the first cities taken by the Islamic State in January 2014.
"The Islamic State cannot be defeated in Anbar unless it is defeated in Fallujah, the city is a symbol for the Islamic State," said Eissa Sayer al-Issawi, Fallujah mayor who was forced to flee the IS onslaught, speaking as he watched the ceremony.
