Complex sentence: During the French occupation of Rome from the end of the 18th century to the start of the 19th century, the church was deconsecrated--it was rebuilt by Francesco Manno between 1814 and 1817.
Split into simpler sentences: During the French occupation of Rome from the end of the 18th century to the start of the 19th century, the church was deconsecrated. It was rebuilt by Francesco Manno between 1814 and 1817.