Complex sentence: He was "Maestro Di Cappella" at St Peter's from 1715 to 1719 and in the latter year came to London to direct his opera "Narciso" at the King's Theatre.
Split into simpler sentences: He was "Maestro Di Cappella" at St Peter's from 1715 to 1719. In 1719 he travelled to London to direct his opera "Narciso" at the King's Theatre.