Karađoz Bey Mosque was built on the foundations of the Catholic church of Saint Stephen the Protomartyr. An Arabic foundation inscription on the mosque records that it was commissioned by Mehmed Beg b. Abu al-Saʿadat’ who was a brother of a vizier in the year AH 965 (1557-58). Some scholars have claimed that the vizier was the grand vizier Rüstem Pasha, but Rüstem Pasha is recorded as having only a single brother, Sinan Pasha.
The mosque may have been designed by the imperial architect Mimar Sinan. It is in the form of a domed cube fronted by a double portico. The three domes of the inner portico are supported by four marble columns. The outer portico has a shed roof resting on small octagonal pillars. The large 10.65 metres dome of the mosque sits on an octagonal fenestrated drum which is supported by eight-pointed arches.
The mosque was severely damaged during World War II, and faced near destruction during the Bosnian War in the early 1990s. However, Karađoz Bey Mosque, like the rest of Mostar, underwent extensive repairs between 2002 and 2004. The mosque was completely renovated and reopened to the public in July 2004.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.