The Basilica of St. Stephen in the Round on the Celian Hill (Basilica di Santo Stefano al Monte Celio), commonly named Santo Stefano Rotondo, is Hungary's 'national church' in Rome. It is dedicated to both Saint Stephen, the Christian first martyr, and Stephen I, the sanctified first king of Hungary who imposed Christianity on his subjects.
The earliest church was consecrated by Pope Simplicius between 468 and 483. It was dedicated to the protomartyr Saint Stephen, whose body had been discovered a few decades before in the Holy Land, and brought to Rome. The church was the first in Rome to have a circular plan, inspired by the Church of the Holy Sepulchre in Jerusalem.
The church was embellished by Pope John I and Pope Felix IV in the 6th century with mosaics and colored marble. The church was restored in 1139-1143 by Pope Innocent II, who abandoned the outer ambulatory, and three of the four side chapels. He also had three transversal arches added to support the dome, enclosed the columns of the central ambulatory with brick to form the new outer wall, and walled up 14 of the windows in the drum.
In the Middle Ages, Santo Stefano Rotondo was in the charge of the Canons of San Giovanni in Laterano, but as time went on it fell into disrepair. In 1454, Pope Nicholas V entrusted the ruined church to the Pauline Fathers, the only Catholic Order founded by Hungarians.
The altar was made by the Florentine artist Bernardo Rossellino in the 15th century. The painting in the apse shows Christ between two martyrs. An ancient chair of Pope Gregory the Great from around 580 AD is preserved here.
The Chapel of Ss. Primo e Feliciano has very interesting and rare mosaics from the 7th century.
The Hungarian chapel is dedicated to King Stephen I of Hungary, Szent István, the canonized first king of the Magyars. The frescoes of the chapel were painted in 1776 but older paintings were recently discovered under them.
Under the church there is a 2nd-century mithraeum, related to the presence of the barracks of Roman soldiers in the neighbourhood. The cult of Mithras was especially popular among soldiers. A coloured marble bas-relief from the 3rd century is today in the Museo Nazionale Romano.
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.