It was constructed in the 6th Century under orders from Pope Pelagius II on the site of Emperor Constantine’s oratory, which Constantine believed was the site where Lawrence was killed. In the 13th Century a new church was constructed in front of the old one in the martyr’s honour and it contained many beautiful frescoes portraying St Lawrence’s life and also that of the first deacon to be martyred, St Stephen. Both deacons are buried beneath the main altar. Eventually the two churches were joined and excavations revealed many other graves, one believed to be that of St Hilarius.

The church also houses two old sarcophagi within the portico. One is believed to date back to the 7th Century. Two statues of Romanesque stone lions also reside at the entrance. Before the entrance lies the tomb of Cardinal Fieschi who died in 1256 and that of Italian Prime Minister and founding father of the European Union, Alcide de Gasperi. His tomb was designed by renowned sculptor Giacomo Manzu. The pulpit and the enclosure for the choir enclosure and pulpit has medieval design as does the Paschal candlestick. Just behind the pulpit one column is decorated with carvings of a lizard and a frog. The Byzantine triumphal arch is decorated with 6th-century mosaics of Jesus with various saints. At the back of the main altar there is an inscription containing the makers’ names; the Cosmati family, which dates this piece to 1148. The church was bombed during the World War II, but was restored.