Pietro Dusina recorded Mosta as a parish in his 1575 pastoral visit; the town actually became a parish in 1608. Plans to construct a new church began soon afterwards, and the church was built in around 1614 to designs attributed to the
Renaissance architect
Tommaso Dingli. This church was commonly called ''Ta' Ziri''. By the 1830s the town's population had become too large for the church.
Giorgio Grognet de Vassé proposed rebuilding the church on a
neoclassical design based on the
Pantheon in Rome. Opposed by Bishop
Francesco Saverio Caruana, the design was approved, and construction of the church began on 30 May 1833. The new church was built around the old church, which remained in use throughout the course of construction. The residents of Mosta helped in building the church, taking part in construction work on Sundays and public holidays. The rotunda took 28 years to build, being completed in the early 1860s. The old church was demolished in 1860, In a bombing by the
Nazi air force on 9 April 1942, during the
Siege of Malta in World War II, a bomb pierced the dome and entered the church. The bomb did not explode, and a
Royal Engineers Bomb Disposal unit defused it and dumped it into the sea off the west coast of Malta. This event was interpreted as a miracle by the inhabitants, and the casing of an identical bomb is now displayed in the sacristy at the back of the church. On 2 May 1983, taxi driver Carmelo Aquilina deliberately drove a
Mercedes car into the Rotunda following a bet. He drove up the steps of the parvis, broke down the main doorway, and stopped within the church close to the altar. Aquilina was arrested and received a three-month prison sentence while his driving licence was suspended. In 2015 the parish asked the Vatican to be reclassified to the status of a
basilica. The church was elevated to a minor basilica on 29 July 2018. ==Architecture==