Final answer:
Holy Roman Emperor Charles V was preoccupied with securing his election and conflicts, leading to a delay in suppressing the Lutheran Reformation.
Step-by-step explanation:
The Holy Roman Emperor who did not move quickly to suppress the Lutheran Reformation at the beginning due to his preoccupation with securing his election as emperor and conflicts with France and the Ottoman Turks was Charles V. While Charles V opposed Protestantism, his attention was often directed towards political and military challenges of his broad dominions. The Peace of Augsburg in 1555 eventually allowed Lutheran rulers within the empire to establish Lutheranism as their official religion if they chose to do so, marking a significant milestone in the history of religious freedom in Europe.