'Ashura is the tenth day of Muharram (the first month of the Islamic calendar). It is the climax of the Muharram mourning rituals which commemorates the martyrdom of Hussain ibn Ali, the grandson of the prophet of Islam, Muhammad at the Battle of Karbala on 10 Muharram in the year 61 AH. For Sunnis, it is a day on which fasting is recommended.
The root of the word Ashura has the meaning of tenth in Semitic languages. The Arabic term derives from the Hebrew word ʿasor with the Aramaic determinative ending -ā. It refers broadly to the first ten days of Muharram, but more specifically to the tenth day.
‘Ashura in Shiʿite piety
After the death of Muawiya in the spring of 60/680, his son Yazid succeeded him as caliph. Yazid’s succession by hereditary appointment rather than election or popular acclaim met with strong opposition in many quarters of a community already torn by conflict and dissension. Among the many dissenting groups was the party (Shiʿa) of ‘Ali b. Abi Taleb, led by his son, Imam Hussain. Hussain’s supporters in Kufa urged him to lead them in revolt against Yazid’s rule; after some hesitation, he answered their persistent entreaties, not simply from political motives, but also because of an idealistic view of Islam that he sought to defend at all cost. His martyrdom has therefore been regarded by Muslims, Sunni as well as Shiʿite, as the model for self-sacrifice in the way of God, a revolt against wrong-doing and oppression. This fact has not been fully appreciated by most Western historians; yet it is crucial for a true understanding of the significance of ‘Ashura for the Muslim community in general, and especially its Shiʿite members.
Hussain left for Kufa with his family and about seventy men. On the second of Muharram, 61/680 he encamped on the plain of Karbala, where he faced an army of about 4,000 men sent to intercept him by the governor of Kufa, ʿObaydallah b. Ziad. After a week of fruitless negotiations, the head of the army, ʿOmar b. Saʿd, put the choice to Hussain and his followers of either surrendering to the authority of Ibn Ziad or fighting. The battle that ensued lasted from early morning to mid-afternoon. Hussain and his followers, including the able male members of his family, were killed; his women and children were led captive first to Kufa, then to Damascus. 
The death of Imam Hussain produced an immediate reaction in the Muslim community, especially in Iraq. When the people of Kufa saw his head and the pitiful state of the captives, they began to weep and beat their breasts in anguish.  Many of them regretted their failure to support Hussain and were filled with remorse; they came to form the movement known as the repenters (al-tawwabun). The chaos and bloodshed that followed gives eloquent testimony to the far-reaching effect of the tragedy of Karbala on subsequent Muslim history. 
Among the few who escaped the massacre of Karbala was Hussain’s only surviving son, ‘Ali Zayn-al-ʿabedin, who was spared on account of sickness; he was soon proclaimed fourth Imam by a considerable segment of the Shiʿite community. His home in Medina became an important center for the growth of the ‘Ashura cults; no doubt his piety, political quietism, and continuous sorrow for the tragedy provided the religious basis of the ‘Ashura celebration.
History of the Commemoration by Shi’a
Commemorative services (majales al-taʿzia) first held in the houses of the imams and their followers, originally consisted of recounting the tragedy, reflecting on its meaning, and reciting elegies (marthia) in memory of the martyred Imam. From the beginning, these majales were not limited to the ‘Ashura days, but were and still are held at any time of the year. Soon the shrines of the imams in Iraq and Iran became important centers of pilgrimage (ziara), where the pious held their lamentations. 
During the Umayyad period, the ‘Ashura cult and the spirit of revolt it fostered grew in secret under persecution and repression. The ʿAbbasid rulers, who came to power on the wave of pro-ʿAlid revolt, at first encouraged and patronized large public assemblies in commemoration of the sufferings of the Prophet’s family (Ahl Al-Bayt) and the tragedy of Karbala. By the end of the 4th/10th century, professional mourners (naʾeh), also known as the reciters or story tellers (qorraʾ) of Hussain, chanted elegies and led the pious in dirges; they normally read martyrdom narratives (maqatel) relating the story of Hussain in all its details.
In 351/962, under Buyid patronage, ‘Ashura was declared a day of public mourning in Baghdad. Processions were held in the streets of the city, markets closed, and shops draped in black.  Special edifices were built for the celebrations of ‘Ashura (called Hussainiya; also tekyeh in Iran), and by the end of the 3rd/9th century these were common in Cairo, Aleppo, and many Iranian cities.
As early as the 5th/11th century Iranian poets composed elegies in his memory. One of the most comprehensive works, in poetry and prose, on the subject in Persian is Rawzat al-Shuhada by a Sunni author, Hussain b. ‘Ali Waʿez Kashefi, (d. 910/1504-05). An outstanding Shiʿite poet was Mohtasham Kashani.  From Iran, the ‘Ashura celebration was carried to the Indian subcontinent and other parts of the Muslim world influenced by Iranian culture. The greatest impetus for the development of the ‘Ashura celebration as a popular religious and artistic phenomenon came with the rise of the Safavids to power in the early 10th/16th century. It was during their rule that the important dramatic genre known as taʿziya was highly developed and popularized.
The ‘Ashura ritual possessed from its inception a dramatic tension. The sufferings and privation of the Ahl al-Bayt are contrasted with their high status with God and the reward they will enjoy in paradise. The weeping of all things for their suffering, and especially for the death of Hussain, is contrasted with the cruelty of their enemies. Finally, the great rewards which the mourners of Hussain will enjoy in the hereafter are sharply contrasted with the torment and remorse which the enemies of the Ahl al-Bayt will suffer on the Day of Resurrection. By the end of the 4th/10th century the main themes and hagiographic tales of the Muharram cultus had taken shape; these were further elaborated and popularized through the taʿziya and the popular orations eventually known as rawza-khani (q.v.). Through their grief and remembrance, the pious vicariously share in the sorrows and sufferings of the Ahl al-Bayt and renew their relation with the imams. This remembrance is powerfully expressed in the ziara ritual, which can be performed either at the shrine of an imam on the day of ‘Ashura or at any time in an open space outside the city or town; it is usually followed by a meal at the homes of well-to-do members of the community, the donation of which is a pious act of great merit.
Very early, Shiʿite Muslims distinguished their observance of the ‘Ashura from both its Jewish and Islamic antecedents. They denied all claims for special favors granted by God on that day to the ancient prophets; hence it is to be observed not as a day of thanksgiving and exaltation, but as one of sorrowful remembrance. It should not be observed as a regular fast day; rather the pious must experience hunger and thirst in emulation of the Imam and his family in Karbala, but must break the fast before sunset. It is to be understood not as a day of blessing, but of chaos and disorder, a day of ill-omen.
This emphasis on mourning in the Moharram cultus has led some scholars to postulate a direct relation between it and the ancient myths and rites of Tammuz-Adonis.  To what extent the ‘Ashura rites could have been influenced across so many centuries by these ancient myths cannot be determined; the fact that Hussain happened to die on the spot where the cult of the ancient god was celebrated is simply an interesting coincidence which proves nothing. Iranian influences on the Muharram cultus have also been suggested by scholars who point to ceremonies in seventh-century Sogdia and Kharazm commemorating the unjust death of the legendary hero Siavosh at the hands of Afrasiab that included breast-beating and the chanting of threnodies  is, in fact, invoked in the text of at least one taʿzia  and there may be other echoes of the Siavosh myth in the Persian taʿzīa literature. It is, however, unlikely that memories of Siavosh should have influenced formatively the Shiʿite mourning ceremonies of ‘Ashura, which originated in areas far removed from Outer Iran and which are perfectly explicable, in any event, in terms of the ethos of Shiʿism.
It is more plausible that any parallels between the various mourning rites are due more to similarities in psychology and a general thematic continuity in mythological development by geographically related cultures. The ‘Ashura cultus in Shiʿite Islam is based on an historical event and commemorated the death not of a god, but of a man who was intensely involved in the life of an actual community. Like other great men and religious heroes, Hussain the martyr continues to live on in the community through poetry, myth, and ritual, but above all through the actual events of the community’s history. Whatever its origins or relations to other religious phenomena, the ‘Ashura cultus is yet another instance in human history of man’s attempt to deal creatively and meaningfully with his ephemeral condition.
- Tabari [Cairo], II, pp. 295-390; Mofid, Ershad, ed. Sayyed Kazem al-Miamawi, Tehran, 1377/1957-58, pp. 215ff., tr. I. K. A. Howard, London, 1981, p. 370.
- Yaʿqubi, ed. M. S. Baḥr-al-ʿolum, Najaf, 1384/1964, II, pp. 231ff.
- J. Wellhausen, The Arab Kingdom and its Fall, tr. M. G. Weir, Beirut, 1963, esp. pp. 147-200.
- Ibn Qawluya, Kamel al-ziarat, ed. Mirza ʿAbdallah Hussain Amini Tabrizi, Najāf, 1356/1937, pp. 325-26.
- ʿAbbas Qomi, Nafas al-mahmum, p. 226, Persian tr. Romuz al-Shahada by M. B. Kamaraʾi, Tehran, 1379/1960; Hebat-al-din Shahrestani, Nahzat al-Hussain, Karbala, 1969, pp. 149ff.
- d. 996/1588; see the translation of his famous haftband in Browne, Lit. Hist. Persia IV, pp. 172-77.
- B. D. Erdmans, “Der Ursprung der Ceremonien des Hosein-Festes,” ZA 9, 1894, pp. 302ff.; Ch. Virolleaud, Le théâtre persan ou le drame de Kerbéla, Paris, 1950, pp. 128-36.
- A. Bausani, Persia Religiosa, Milan, 1959, pp. 420-21; E. Yarshater, “Taʿziyeh and pre-Islamic mourning rites in Iran,” in Taʿziyeh: Ritual and Drama in Iran, ed. P. Chelkowski, New York, 1979, pp. 88-94). The “blood of Siavosh” (khun-e Siavosh.
- C. Virolleaud, Le théâtre persan, p. 132.
- See also Maǰlesī, Jalāʾ al-ʿoyūn, Tehran, 1372/1952, pp. 305ff.
- M. T. Lesān-al-molk Sepehr, Nāseḵ al-tawārīḵ VI/2, Tehran, 1343/1924.
- G. E. von Grunebaum, Muhammadan Festivals, New York, 1951, pp. 85-94.
- M. Ayoub, Redemptive Suffering in Islam: A Study of the Devotional Aspects of ʿĀshūrāʾ in Twelver Shīʿism, The Hague, 1978.