You are going to have to narrow your question down to a date span, like a particular century, and a particular country or at least an area: like, for instance, English monarchs in the 16th century.
Monarchs, the church, and the Crusades were intertwined in medieval Europe. Monarchs often worked closely with the church to validate their rule and gain divine support. The Crusades were military campaigns sanctioned by the church, led by monarchs, with the goal of reclaiming the Holy Land from Muslim control. This collaboration between all three entities shaped the power dynamics and religious landscape of Europe during this period.
The church constantly threatened the monarchy with excommunication when they went against the church. In the Middle Ages excommunication was a real threat to people because they believed that they would go to Hell if they didn't follow the church.
They ate the ground
It made the Church dependent on individual monarchs.
The pope and the clergy tried to preserve Chruch privileges as powerful monarchs chipped away at it's power.
It started killing the people
buy building more church take over the church and have more law
All British Monarchs are Church of England Anglicans and part of their royal title is Defender of the Faith.
the pope's wealth
All British Monarchs are Church of England (Anglican protestants). The British Monarch is by law the head of the Church of England.
the selection of Church officials.
Westminster Abbey