There were several conversions to Catholicism of the Latin rite, and this led Congregation for the Evangelization of Peoples to establish a diocese in Aleppo.

On 31 July 1645 was appointed bishop the Franciscan Giovanni Battista Dovara, which, however, "that he had achieved such a dignity, otherwise do not bother to go to his residence, despite the replicated excitations that he was moved by the Holy Congregation.

[3]: 300  The vicariate so he died in the bud: the jurisdiction of the Latin returned to the Custodian of the Holy Land (traditionally a Franciscan), as it was previously.

It had jurisdiction over much of Catholic missions of the central and southern regions of the Ottoman Empire, namely : Syria, Lebanon, Cyprus, Palestine, the Arabian Peninsula, Egypt, Abyssinia (then empire of Ethiopia including Eritrea) and Nubia (Anglo-Egyptian Sudan and southernmost Egypt).

On October 4, 1847, it ceded Palestine, Cyprus and the areas corresponding to (the current / (Trans)Jordan for the restoration of the Latin Patriarchate of Jerusalem.

With the end of the Ottoman Empire, the birth of modern Turkey (1923) and especially with the passage of Hatay from Syria to Turkey (1938), under the Papal bull of Pope Pius XII Ad maius christifidelium of 5 October 1939 and Quo sacrorum of 9 December 1939, the Vicariate Apostolic of Aleppo lost the Turkish territories that passed to the Apostolic Vicariate of Istanbul.