St. Martin's Church () is a Roman Catholic church in Split, Croatia. Built into a small space (an early guardhouse) within the ancient Golden Gate of Diocletian's northern wall, it is one of the oldest churches in the city. St. Martin's Church is one of Split's tourist attractions and is known for its fine 11th century chancel screen. It is currently in the care of the Dominican sisters, who have a monastery next door. The church itself is open to public visits.
History
St. Martin's is located in a cavity of the west wall above the Porta Aurea of Diocletian's Palace. That space, in the time of Diocletian (285-305), was a narrow corridor (1.64 meters wide by 10 meters long) that was used as a guardhouse, with the windows (now filled in) on the south side for surveillance of approach to the main gate into the complex. These windows remain well preserved to the present day in their original form, while windows on the north side date from the city's defence against the Ottoman Turks in the 15th century. The space was converted into a church sometime in the 6th century when the complex saw an influx of refugees from outlying communities. Similar churches exist/existed over the Silver Gate, Iron Gate, and the Bronze Gate.
An inscription along the architrave of the entrance door: REX BENEDICTE D(EU)S, LAUDIS DECUS IMPERI V(IRTUS)Q(UE. (H)ANC (ECCLESIAM) CONSTITUIT SUB (H)ONORE(M) BEATI MARTINI (H)UMIL(I)TE(R) (HA)EC ATQ(UE) POTE(N)S P(RES)B(Y)T(E)R DOMINICUS. SALVE PA(TER)...T TIBI P(ER) N(OST)RI PECTORIS ANTRA COLI.
Translated by archaeologist Frane Bulić, it reads:
In identifying Dominic, Bulić dated the inscription to the ninth century and the region of Trpimir I. It seems the (knez) chaplain Dominic renovated the former guardhouse into the first Christian church in the city dedicated to the Virgin Mary, Saint Gregory I and St. Martin of Tours (the father of western monasticism).
On 4 March 852 Trpimir issued a charter in Biaći (in loco Byaci dicitur) in the Latin language, confirming Mislav's donations to the Archbishopric in Split. The charter is preserved in a copy from 1568. In this document, Trpimir named himself "by the mercy of God, Duke of the Croats" () and his realm as the "Realm of the Croats" (Regnum Chroatorum). The term regnum was used by other rulers of that time as a sign of their independence and did not necessarily mean a kingdom. The charter documents Trpimir's decision to build a church (possibly St Martin's) and the first Benedictine monastery in Rižinice, thus bringing the Benedictins into Croatia.
On the architrave, together with his own name, Trpimir also had the name of his other chaplain (also called Martin). The Main altar too dates from the 9th century. The church later provided certain amenities such as a settlement for Dominican sisters (which dates as far back as the 14th century). Bulić, following his discoveries of 1890 and study of the palace, recommended its renovation. On that occasion, the new altar and nave were built. In 1929, during the enlargement of one of the windows, a tablet was discovered with an engraved inscription: "The unworthy servant, priest Dominic, chaplain of Duke Trpimir". Bulić believed that this might represent the gravestone of Dominic. Today it is kept in the Archaeological Museum.
Above the church, a pre-Romanesque bell tower was erected, which was later demolished in the 19th century (similar to the church bell tower of Our Lady of Zvonik above the Iron Gate, which has been preserved to date).