Frederick II (German: Friedrich II.; 24 January 1712 – 17 August 1786) was a Prussian royal, military leader, writer, and composer who was King of Prussia from 1740 until his death in 1786. He was the longest reigning monarch of the House of Hohenzollern. His most significant accomplishments during his reign included his military successes in the Silesian wars, his reorganisation of the Prussian Army, the First Partition of Poland, and his patronage of the arts and the Enlightenment. Frederick was the last Hohenzollern monarch titled King in Prussia and declared himself King of Prussia after annexing strategic parts of the Polish–Lithuanian Commonwealth in 1772. Prussia greatly increased its territories and became a leading military power in Europe under his rule. He became known as Freder