We study the effect of divisions within the elite on the probability of internal conflict in the Papal States between 1295 and 1846. We assemble a new database using information on cardinals that participated in conclaves during this period, and construct measures of polarization and fractionalization based on the cardinals’ birthplaces. We find that an increase of one standard deviation in our measure of polarization raised the likelihood of internal conflict by between 3 and 4 percent in a given year and by up to 24 percent in a given papacy. The effect is largest in the initial years after the conclave, to gradually vanish over time. Our results confirm that cardinals’ influence on the politics of the Papal States decreased after reforms introduced between 1586 and 1588. These reforms successfully attenuated the political consequences of divisions among cardinals, the elite of one of the largest and oldest organizations.