Shi'ah (or Shi'ite) a Muslim sect which believes that the caliphate succession should follow the line of the family of the Prophet muhammad (Sm) beginning with Hazrat Ali (R), the son-in-law of the Prophet. 'Ali, who failed to obtain nomination to the caliphate after the death of the Prophet, was elected to the post in 656 AD. However, the succession was fiercely opposed by Mu'awiyah, a relative of Hazrat Uthman (R), the third caliph. 'Ali was assassinated in 661 and succeeded by his son, Hasan, who, however, was later forced to cede the caliphate to Mu'awiyah. Hasan died shortly thereafter, allegedly poisoned. Following the death of Mu'awiyah, Husain, the brother of Hasan, expected to become caliph, but Mu'awiyah's son Yazid, whom Mu'awiyah had named to succeed him, became caliph. Husain led an unsuccessful revolt against Yazid and was killed at Karbala.

The fate of Hazrat Ali (R) and his sons inspired the rise of the Shiahs, who believe that Ali had a special spiritual function alongside that of the Prophet which gave him and his descendants the right to spiritual leadership. This function was passed on by Hazrat Ali (R) to his descendants who are the imams. The Shiahs, believe that there are twelve imams, beginning with Hazrat 'Ali (R) and his sons Hasan and Husain and ending with the twelfth imam who is still alive and will return just before the world ends.

Shi'ism, which was initially a political issue, slowly developed into a sacred dogma which gained ground under the 'Abbasids when open expression of Shi'ite thought and activities was permitted. In 962 formal public mourning of Husain as a martyr was instituted. It was finally in the 16th century, when the Safavid dynasty came to power in Persia, that Shi'ism began to be propagated with missionary zeal. The Safavid rulers made Shi'ism the state religion of Persia.

Apart from the status of Hazrat 'Ali (R) and his sons and the idea of the living imam, Shiahs and Sunnis differ doctrinally on a number of points. Some differences, for example, pertain to prayer; for example, in the adhan, or call to prayer, Shiahs add the line: Aliyyu waliyyullah (Ali is the friend/ saint of God). They also add the line: Hayya ala khayri-l-amal (rise up for the best works) twice, which they believe was originally part of the prayer. Moreover, after the iqamah (a repetition of the adhan) and during the qiyam (standing position), Sunnis fold their hands in front, while Shi'ahs let their hands hang on either side. After Sunnis fold their hands, they do not raise them while saying Allahu Akbar. Shiahs, however, raise their hands every time. They also systematically combine the two afternoon prayers.

Shi'ism reached Bengal in the early 17th century via Persia when Persian traders and adventurers propagated Shi'ism in Bengal. shah shuja, the Mughal governor of Bengal, was a Sunni but he patronised Shi'ism. His mother, Mumtaz Begum, was a Shiah. Many of the amirs in his darbar came from Persia and were Shiahs. All the nawabs in the early 18th century belonged to the Shiah sect. With their patronage the Shiah sect began to expand in Bengal. The first ten days of the month of muharram were declared as holidays by murshid quli khan in honour of the martyrdom of Imam Husain and his followers. Over time, Muharram turned out to be one of the biggest festivals of Bengal. To please the nawabs and the Shiah nobility, even Hindu zamindars used to promote the Muharram festival very actively. For example, the most attractive tazias and ta'ziah processions in the province used to be organised by the rajas of Natore and Burdwan. In every kachari of the large zamindars, ta'ziah processions were taken out, accompanied by music. Such ta'ziah processions drew the attention of foreign visitors, many of whom drew sketches of these processions.

The naib nazims of Dhaka were Shiahs, and, with their patronage, the Muharram festival became popular in East Bengal though the Muslims of this province were, and are, by and large Sunnis. nawab khwaja abdul ghani, the founder of the present nawab family of Dhaka, observed Muharram in his kachari very elaborately though he was a Sunni. The tradition of observing Muharram by the nawab family continued down to the end of the zamindari system in 1950. The husaini dalan Imambara, which was built by a Shiah merchant in the 18th century, is now the main centre of Muharram observances of the Shiah community in Dhaka.

In Bangladesh, the Shiahs are an urban minority. Recently, the traditional peaceful co-existence of Shiahs and Sunnis appears to be declining. The ta'ziah processions, which were hitherto participated in by the Muslims of both sects, are now organised only by the Shiahs. During the British period, their processions came under attacks from the Hindus. In fact, many of the Hindu-Muslim riots in the late 19th and early 20th centuries were occasioned by ta'ziah processions passing by Hindu temples. The differences between Shiah and Sunni Muslims, which were shelved during the anti-British agitation, have, however, again surfaced, occasionally with bad results. [Niaz Zaman]