Two shrines inside the premises commemorate the Islamic prophet Muhammad's grandson Husayn ibn Ali, whose martyrdom is frequently compared to that of John the Baptist and Jesus.

When the empire in Syria transitioned to Christian Byzantine rule, Emperor Theodosius I (r. 379–395) transformed it into a cathedral and the seat of the second-highest-ranking bishop in the Patriarchate of Antioch.

The new structure was built over nine years by thousands of laborers and artisans from across the Islamic and Byzantine empires at considerable expense and was funded by the war booty of Umayyad conquests and taxes on the Arab troops of Damascus.

The mosque was noted for its rich compositions of marble paneling and its extensive gold mosaics of vegetal motifs, covering some 4,000 square metres (43,000 sq ft), likely the largest in the world.

Although the original structure has been altered several times due to fire, war damage, and repairs, it is one of the few mosques to maintain the same form and architectural features of its 8th-century construction, as well as its Umayyad character.

Damascus was the capital of the Aramaean state Aram-Damascus and a large temple was dedicated to Hadad-Ramman, the god of thunderstorms and rain, and was erected at the site of the present-day mosque.

[1] The Temple of Hadad-Ramman continued to serve a central role in the city, and when the Roman Empire conquered Damascus in 64 BCE, they assimilated Hadad with their own god of thunder, Jupiter.

[4] The Temple of Jupiter would attain further additions during the early Roman period, mostly initiated by high priests who collected contributions from the wealthy citizens of Damascus.

[16][21] The historian Khalid Yahya Blankinship notes that the field army of Damascus, numbering some 45,000 soldiers, were taxed a quarter of their salaries for nine years to pay for its construction.

However, at least two of the corners of the mosque's outer wall had short towers, platforms, or roof shelters which were used by the muezzin to issue the call to prayer (adhān), constituting a type of proto-minaret.

[a] By some estimates, the original mosque had the largest area of gold mosaics in the world, covering approximately 4,000 square metres (43,000 sq ft).

[38] In addition to the large landscape depictions, a mosaic frieze with an intricate vine motif (referred to as the karma in Arabic historical sources) once ran around the walls of the prayer hall, above the level of the mihrab.

[38] Historical Arabic sources, often written in later centuries, suggest that both the craftsmen and the materials employed to create the mosque's mosaics were imported from the Byzantine capital of Constantinople.

[41][42][43] The 12th-century historian Ibn Asakir claimed that al-Walid pressured the Byzantine emperor into sending him 200 craftsmen by threatening to destroy all churches inside Umayyad territory if he refused.

[44][45] Many scholars, based on such evidence from Arabic sources, have accepted a Byzantine (Constantinopolitan) origin for the mosaics,[46][47] while some, such as Creswell, have interpreted the story as a later embellishment of Muslim historians with a symbolic political significance.

[50] Some scholars argue that the mosaic techniques in both the Dome of the Rock and the Umayyad Mosque, including their distinctive colour scheme, are more clearly consistent with the craftsmanship of Syro-Palestinian or Egyptian mosaicists.

[38] Some of the Qur'anic inscriptions that were originally present on the qibla wall of the mosque, mentioning the Day of Judgment and promising the reward of a heavenly garden (al-janna), may support this interpretation.

[67][68] The 10th-century Jerusalemite geographer al-Muqaddasi credited the Abbasids for building the northern minaret (Madhanat al-Arous, meaning 'Minaret of the Bride') of the mosque in 831 during the reign of Caliph al-Ma'mun (r. 813–833).

The Umayyad Mosque's prestige allowed the residents of Damascus to establish the city as a center for Sunni intellectualism, enabling them to maintain relative independence from Fatimid religious authority.

[72] In 1069, large sections of the mosque, particularly the northern wall, were destroyed in a fire as a result of an uprising by the city's residents against the Fatimids' Berber army who were garrisoned there.

[74] In 1082, his vizier, Abu Nasr Ahmad ibn Fadl, had the central dome restored in a more spectacular form;[75] the two piers supporting it were reinforced and the original Umayyad mosaics of the northern inner façade were renewed.

[79] In Damascus there is a mosque that has no equal in the world, not one with such fine proportion, nor one so solidly constructed, nor one vaulted so securely, nor one more marvelously laid out, nor one so admirably decorated in gold mosaics and diverse designs, with enameled tiles and polished marbles.

[87] However, the Muslim Mamluks of Egypt, led by Sultan Qutuz and Baybars, wrested control of the city from the Mongols later in the same year, killing Kitbuqa in the Battle of Ain Jalut, and the purpose of the Mosque was returned from Christian to its original Islamic function.

By 1650 members of the mercantile and scholarly Mahasini family held the position, retaining it for much of the 18th and early and mid-19th centuries, partly due to their links with the Shaykh al-Islam in the imperial capital.

[107][39][24] Until 1899 the mosque's library included the "very old" Qubbat al-Khazna collection;[109] "most of its holdings were given to the German emperor Wilhelm II and only a few pieces kept for the National Archives in Damascus.

[113] In 1990s, Mohammed Burhanuddin constructed a zarih of the martyrs of the Battle of Karbala,[114] whose heads were brought to the Mosque after their defeat at the hands of the then Umayyad caliph, Yazid I.

[115] On March 15, 2011, the first significant protests related to the Arab Spring and eventually the Syrian civil war began at the Umayyad Mosque when 40–50 worshippers gathered outside the complex and chanted pro-democracy slogans.

[141] It holds great significance to Shia and Sunni Muslims, as this was the destination of the ladies and children of the family of Muhammad, made to walk here from Iraq, following the Battle of Karbala.

[143] Two shrines commemorating the Islamic prophet Muhammad's grandson Husayn ibn Ali, whose martyrdom is also compared in Shi'a tradition to that of John the Baptist,[144] exist within the building premises.

[145] According to one hadith reported by Muslim ibn al-Hajjaj,[146] the Great Mosque of Damascus is the site where Jesus will descend from heaven at his Second Coming, appearing on a "white minaret".