Why did Pope Boniface VIII issue the papal bull Unam Sanctam?

A) Secular rulers were challenging his authority.
B) France had invaded Rome.
C) France and England asked the pope to settle a disagreement over colonies.
D) The Ottoman Empire had invaded the Holy Roman Empire.
E) The Holy Roman Empire declared that all its people were Protestants.

Papal Bull Unam Sanctam

A significant papal decree issued by Pope Boniface VIII in 1302, asserting the supreme spiritual authority of the Pope over kings and secular rulers.

Pope Boniface VIII

A Pope who reigned from 1294 to 1303, known for his conflicts with secular rulers and for issuing the Unam Sanctam, asserting papal supremacy.

Secular Rulers

Leaders or monarchs who hold authority in the political realm without specific endorsement from religious institutions.