Question

a string of invasions by the catholic church into the east
the inquisition
the council of trent
alexander’s march
the crusades

Explanation:

The Crusades were a series of religiously - motivated military campaigns (invasions) launched by the Catholic Church (Western Europe) into the East (primarily the Holy Land). The Inquisition was mainly about religious persecution within Europe, the Council of Trent was a reform council, and Alexander’s march was by Alexander the Great (not related to the Catholic Church’s invasions into the East).

Answer:

The Crusades