Complex sentence: A Fiat Campagnola was used during transit within Vatican City and during masses at St. Peter's Square, but following the attempted assassination of Pope John Paul II in 1981, the popemobile was fitted with bulletproof glass on four sides.
Split into simpler sentences: A Fiat Campagnola was used during transit within Vatican City and during masses at St. Peter's Square. But following the attempted assassination of Pope John Paul II in 1981 the popemobile was fitted with bulletproof glass on four sides.