The man whose writings and friendship influenced Catherine II of Russia Frederick II of Prussia and Joseph II Holy Roman Emperor was?

The man whose writings and friendship influenced Catherine II of Russia, Frederick II of Prussia, and Joseph II Holy Roman Emperor was Voltaire. A prominent Enlightenment philosopher, Voltaire advocated for civil liberties, religious tolerance, and the separation of church and state. His correspondence with these leaders helped shape their reformist ideas and promote Enlightenment principles across Europe. Through his wit and intellectual rigor, Voltaire significantly impacted the political and cultural landscape of his time.