Frederick the Great, the king of Prussia from 1740 to 1786, saw himself as a leader of the Enlightenment and patronized philosophers and scientists at his court in Berlin. Voltaire, who had been imprisoned and maltreated by the French government, was eager to accept Frederick's invitation to live at his palace. Frederick explained, "My principal occupation is to combat ignorance and prejudice ... to enlighten minds, cultivate morality, and to make people as happy as it suits human nature, and as the means at my disposal permit."