Industriae tuae is a papal bull of Pope John VIII, issued in June of 880, which the Pope sent to Prince Svätopluk as a reaction to the Great Moravian delegation being sent to Rome. This document legitimatizes the political power of the king, who is greeted as a sovereign. The work itself is addressed to "the beloved son of Svätopluk, the famous count". The Popes declared Great Moravia a fief of the Holy See, which meant that he put Great Moravia on par with other European states of the period, including the Carolingian states in France and Germany. This work also confirmed the role of St. Methodius as a Latin missionary.