With the Faqih Muhammad b. ‘Isa as his source, al-Razi stated that when the Muslims conquered al-Andalus, they followed the examples of Abu ‘Ubayda and Khalid (may God be pleased with them), according to the instruction of the Commander of the Faithful ‘Umar ibn al-Khattab (may God be pleased with him) regarding the partition of Christian churches like the Damascus church and others that the Muslims took peacefully. Thus, the Muslims shared the great church in the city center with the non-Arabs of Córdoba. The Muslims established a congregational mosque in their half; the other portion stayed in the Christians’ hands, and the rest of their churches were destroyed. When the number of Muslims in al-Andalus grew, Córdoba’s population expanded, and the Arab emirs arrived with troops, the mosque became too small for them. Aisles were added but the people still suffered from the lack of space. When ‘Abd al-Rahman (I) ibn Mu’awiya came to al-Andalus and settled in Córdoba, he investigated the matter of the mosque, wishing to enlarge it and improve its buildings. He invited the non-Arabs of Córdoba and asked them to sell the portion of the church which was still theirs. He paid them, in fulfillment of the pact, and permitted them to rebuild the churches that had been demolished at the time of the conquest, outside of Córdoba. Thus, they left the structure, and he took it and extended the great mosque into it. ‘Abd al-Rahman, (called) al-Dakhil, began the demolition of the church and the building of the mosque in the year 169 [785/6]; its construction was finished, its floor tiles laid, and enclosure walls were complete in the year 170 [786/7]—a period of one full year. It was said that ‘Abd al-Rahman spent 80,000 wazina in building the mosque that year.  (Trans. Assia Lamzah, II: 229-30)

[Second excerpt] His son Hisham completed the addition of a minaret, whose height reached 40 cubits at the point where the call to prayer was made. At one end of the mosque he also added galleries for women’s prayer and on the eastern side of the mosque he ordered the construction of ablution fountains. The mosque remained that way until the days of ‘Abd al-Rahman (II) b. al-Hakam who made an addition that was 50 feet long and 105 wide, with 80 columns. This addition was completed in the month Jumadah I in the year 234 (December 848). Then the emir Muhammad b. ‘Abd al-Rahman ordered the perfection of the mosque, the embellishment of its ornament, and the addition of the maqsura. He also made three (new) doors for it. When what he had ordered was finished, he entered the mosque and prayed there...The amir al-Mundhir b. Muhammad added the bayt al-mal (treasury) of the mosque. ...He also ordered the renovation of the water canal and roofs. His son amir ‘Abd Allah b. Muhammad added a bridge (sabat) to link the palace to the mosque on the latter’s western side, aligned with the mihrab. He opened a door into the maqsura that he used to enter for prayer, being the first of the Umayyad emirs of al-Andalus (may God have mercy upon them) to do that. (Trans. Assia Lamzah, II: 230)

Reference

Ibn ‘Idhari, Histoire de l-Afrique du Nord et de l'Espagne musulmane: intitulée Kitab al-bayan al-mughrib, et fragments de la chronique de ‘Arib, ed. G. S. Colin and E. Lévi-Provençal, 2 vols. Leiden: E. J. Brill, 1948-51.