The extremist Sunni group known as the Islamic State of Iraq and Greater Syria (ISIS) on Sunday declared a new caliphate — or an Islamic state to claim dominion over Muslims across the globe — on the territory it holds in the two countries.

An online statement declared the group’s shadowy leader, known as Abu Bakr al-Baghdadi, the Caliph, or successor to the Prophet Mohammed, who died in 632. The position has been vacant since 1924, when the founder of modern Turkey abolished the office as a remnant of the Ottoman Empire, and bundled the last man to hold it, a bookish Francophile named Abdulmecid Efendi, into exile aboard the Orient Express.

Restoring the caliphate, and with it a measure of the glory that attended Islam’s golden age, has been the stated goal of Sunni Muslim activists for decades, from the Muslim Brotherhood to Hizb ut-Tahrir to Osama bin Laden’s al-Qaeda. But al-Baghdadi’s group is the first to assert it. “The time has come for those generations that were drowning in oceans of disgrace, being nursed on the milk of humiliation, and being ruled by the vilest of all people, after their long slumber in the darkness of neglect — the time has come for them to rise,” said the statement.

“They are saying that they are now the center of gravity in global jihad,” says Hayder Al-Khoei, a specialist on Iraq at Chatham House, a London think tank. “They have leap-frogged in that sense al-Qaeda.”

The most immediate tangible effect of the announcement, attributed to ISIS spokesman Mohammed al-Adnani, was to shorten the group’s name. It now wants to be called simply Islamic State, moving past debates over transliterations of the former title, sometimes rendered as ISIL, for Levant instead of Syria, or al-Shams. Social-media sites like Twitter, which the group has used expertly to amplify its message and sense of a strong following, came alive with a new #IS hashtag, while Facebook carried posts claiming to document celebrations — shooting in the air from pickups — in the streets of Raqqa, the Syrian city the Islamist group has held the longest.

Any further impact will depend on public reaction. In the immediate wake of the announcement, skeptics were not hard to find.

The world, after all, is pretty well organized as nation states, the governing concept that admirers of the caliphate reject. “To me,” says al-Khoei, “it sounds like a publicity stunt.”

Even if it is, it might pay off. It’s not hard to imagine Sunday’s announcement, at the start of the Muslim holy month of Ramadan, inspiring young Muslims already inclined toward jihad. “If they’re a caliphate now, a lot of people, possibly living in America or Europe — the ones who are already radicalized and inclined to join them, it’s more of an impetus,” al-Khoei tells TIME. “Maybe the publicity stunt will affect recruiting in that sense. There’ll be more eager, young volunteers excited by the sense that it’s here now, it’s a reality now.”

The fact is, a certain nostalgia for the caliphate lingers in much of the Muslim community — and not only among fundamentalists, or so-called takfiri groups like ISIS that see Shi‘ite Muslims as apostates. Catholics still have their Pope, these mainstream believers point out, and Eastern Orthodox Christians their patriarch.

But there are Caliphs and there are Caliphs. And while many, like the current Christian leaders, preach peace, the summons from the Mesopotamian desert Sunday was to “greedily drink the blood” of nonbelievers according to an early translation posted online:

“The sun of jihad has risen … The glad tidings of good are shining. Triumph looms on the horizon. The signs of victory have appeared. Here the flag of the Islamic State, the flag of tawhīd (monotheism), rises and flutters. Its shade covers land from Aleppo to Diyala.

… So rush O Muslims and gather around your khalīfah [caliphate], so that you may return as you once were for ages, kings of the earth and knights of war. Come so that you may be honored and esteemed, living as masters with dignity. Know that we fight over a religion that Allah promised to support. We fight for an ummah [global Muslim community] to which Allah has given honor, esteem, and leadership, promising it with empowerment and strength on the earth. Come O Muslims to your honor, to your victory. By Allah, if you disbelieve in democracy, secularism, nationalism, as well as all the other garbage and ideas from the west, and rush to your religion and creed, then by Allah, you will own the earth, and the east and west will submit to you. This is the promise of Allah to you. This is the promise of Allah to you.”

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