This week's Arab summit in Baghdad will be very different from the one that met two years ago, with many long-time autocrats swept away by the political tsunami that has struck across the region.

Instead, new Islamist leaders will sit alongside long-serving hereditary rulers, while one country returns having lost much its territory to a newly created state, and all in meetings led for the first time by a Kurd.

On March 28, 2010, leaders of the 22-member Arab League met in Sirte, the home town of late Libyan strongman Moamer Kadhafi.

At the time, the focus of discussion was Israeli settlement-building in the Palestinian territories, and they agreed to next meet in Baghdad in March 2011.

But before then, mass protests erupted, first in Tunisia, that radically changed the Arab world and delayed the Iraqi gathering.

Uprisings in Tunisia and Egypt drove Zine El Abidine Ben Ali and Hosni Mubarak from power respectively, Kadhafi was killed after a months-long rebellion, and Yemen's Ali Abdullah Saleh this year handed power to his deputy after nearly a year of protests and clashes.

Sudan also saw a massive chunk of what was its southern territory separate into newly formed South Sudan.

Syria, meanwhile, has been suspended from the League for its bloody crackdown on a year-long revolt that monitors say has left at least 9,100 people dead, and Damascus has been subjected to wide-ranging sanctions, with Western and some Arab leaders insisting that President Bashar al-Assad's days are numbered.

But there have also been deeper changes, according to one analyst.

"This is a result of the Arab tsunami," said Antoine Basbous, head of the Paris-based Observatory of Arab Countries.

"Heads of state are terrified of their people, and the reverse is no longer true... There will be a real mixing of the old and the new guards."

Triggered by an altercation between a policewoman and a roadside fruit seller who burned himself to death in protest in the Tunisian town of Sidi Bouzid in December 2010, the Arab Spring has also touched countries that escaped mass uprisings.

Popular protests still take place in Bahrain, although rallies there last year were crushed by the monarchy, while parts of Saudi Arabia have also seen demonstrations organised by the kingdom's minority Shiite Muslims.

And in several of the countries where the protesters, often Internet-savvy youths, prevailed, autocrats have been replaced by Islamists who were either repressed or shut out of politics by those countries' now-deposed leaders.

The changes have created new fissures within the Arab League.

Islamist political blocs have fared well in elections in Tunisia, Egypt and Morocco, are the main political force in Yemen, play a major role in Libya, and are expected to do well should Assad's regime fall in Syria.

The arrival of several new Islamist leaders and politicians could give the League a more Islamist identity, after decades of the bloc promoting pan-Arab nationalism.

The small, wealthy emirate of Qatar, meanwhile, sits at the head of an Arab League committee dealing with events in Syria, and is leading calls for armed intervention in that country's conflict.

And tensions between Sunnis and Shiites in the region have rarely been so acute.

The summit will also see what Iraqi officials have described as the re-emergence of their country as a regional leader, after decades of conflict and sanctions following its last turn as host, just months before now-executed dictator Saddam Hussein's 1990 invasion of Kuwait.

"It will be interesting to watch the interplay between Iraq and new leaders in Egypt, Tunisia and Libya," said Reidar Visser, an Iraq analyst and editor of the www.historiae.org website.

"Iraq is interested in reaching out to those countries at the expense of the conservative Gulf states."

The summit will take place despite ongoing violence in Iraq, albeit markedly less than in 2006 and 2007 when all-out sectarian war blighted the country.

Much of the capital has been shut down as part of security efforts, and the government has declared a week-long holiday to cover the period of the summit, encouraging people to stay at home.

Whether or not the security measures deter attacks, they may also have the consequence of reducing interaction between the various Arab delegations.

"The summit will be minimal -- no more than a dozen heads of state spending no more than 12 hours in Baghdad on March 29, and departing on the day of their arrival without spending the night," Basbous said.