One fundamental misunderstanding is the idea that Shi‘ism is somehow intrinsically "Persian," because of its contemporary association with Iran. Misunderstood by whom? I can think of at least three major groups:
- Westerners who know enough about Islam to understand the differences between Sunni and Shi‘a, but who have a fairly superficial knowledge;
- Most Sunni Arabs, at least those from countries without a large Shi‘ite population;
- Most Iranian Shi‘a.
Shi‘ism was, in its origins, as Arab as Sunnism. It was born in Medina, nurtured in Kufa and had its great martyrdom on the field of Karbala'.
Of the 12 Imams of Twelver Shi‘ism, only one, ‘Ali al-Rida (‘Ali Reza), the eighth Imam, is buried in Iran (at Mashhad). The twelfth Imam disappeared in Iraq, and the other ten Imams are buried in Saudi Arabia or Iraq: ‘Ali, the central figure of Shi‘ism, is buried in Najaf, Iraq; Hasan, the second Imam, is buried in Medina; Husayn, the third, is buried where he fell at Karbala' in Iraq; the fourth, ‘Ali Zayn al-‘Abidin, is buried in Medina, while the fifth and sixth are also buried in Medina; the seventh and ninth are buried at the Qazimiyya shrine attacked last Friday in Baghdad; the tenth and eleventh are buried in the al-‘Askari shrine in Samarra' (blown up in 2006, starting a wave of sectarian killing); the twelfth disappeared in Samarra' as well.
The reason there were so many Iranian pilgrims killed in the attacks in Iraq (leading Iran to blame them on the US and Israel, though clearly Sunni radicals were responsible) is that most of the major shrine mosques of Shi‘ism are in Iraq, final resting place for six of the twelve Imams.
The close identification of Iran with Shi‘ism really only dates from the 16th century, when Safavid Iran officially adopted Twelver Shi‘ism as its faith. While there had been earlier Shi‘ite dynasties there, Shi‘ite dynasties of one kind or another flourished in many Arab countries. Cairo's ancient Fatimid gate, the Bab al-Nasr, even has an inscription reading "There is no God gut God; Muhammad is the Prophet of God and ‘Ali is the wali of God," the Shi‘ite formulation of the Muslim shahada. (The Fatimids, though, were Isma‘ili Shi‘ites, not the Twelver variety found in Iran, Iraq, etc.)
Until Saddam Hussein began really cracking down on the Shi‘ite clerical establishment during the Iran-Iraq war (again, the suspicion of Shi‘ites as a fifth column), Najaf was the most important scholarly center for Shi‘ite theology; it was where the Ayatollah Khomeni himself taught in exile from Iran. With the Iranian Revolution and Saddam's crackdowns, the importance of Najaf declined and Qom, Mashhad, and other Iranian clerical schools became suppliers of clerics to Shi‘ites in other countries; with that came some genuine Iranian influence (such as with Hizbullah in Lebanon), but most Arab Shi‘ites are Arabic-speakers, not Persian-speakers.
As I said though, many Sunnis assume Arab Shi‘ites are somehow more Persian than they are, and many Iranians are surprised when Arab Shi‘ites do not avidly follow the Iranian model of clerical rule. Iraqi Shi‘ites rightly and proudly consider their country the seedbed of Shi‘ite Islam.