This study analyses the Proclamación Católica (Catholic Proclamation) by Gaspar Sala under a catholic point of view, which is the name giver to the work, an aspect not taken into account so far by the studies of this work and of the Catalan revolt in general. In consequence, the analysis is based on the concept of catholic monarchy, an identity the monarchy adopts at the beginning of the 17th century. After clarifying this concept and its differences from the title of catholic monarch, the work is analyzed in three parts. The first one consists in a contrast of the Catalans as catholic vassals and the king’s soldiers as sacrilegious vassals. The second one compares the same Catalans as good vassals to the bad king’s ministers in charge of the government of the monarchy. Finally, the third part is a summary of Catalan history as an elective monarchy. We conclude that for the three parts it is necessary to take into account the background of the concept of catholic monarchy in order to achieve an accurate interpretation of the work.