Ferdinand III (13 July 1608 – 2 April 1657) was Holy Roman Emperor from 15 February 1637 until his death, as well as King of Hungary and Croatia, King of Bohemia and Archduke of Austria.
Ferdinand was born in Graz, the eldest son of Emperor Ferdinand II of Habsburg and his first wife, Maria Anna of Bavaria. Educated by the Jesuits, he became King of Hungary in 1625, King of Bohemia in 1627 and Archduke of Austria in 1621.
In 1627 Ferdinand enhanced his authority and set an important legal and military precedent by issuing a Revised Land Ordinance that deprived the Bohemian estates of their right to raise soldiers, reserving this power solely for the monarch.
Following the death of Wallenstein (who had previously denied him the overall military command of the Catholic side) in 1634, he was made titular head of the Imperial Army in the Thirty Years' War, and later that year joined with his cousin, the Cardinal-Infante Ferdinand, being nominally responsible of the capture of Donauwörth and Regensburg, and of defeat of the Swedes at the Battle of Nördlingen. Leader of the peace party at court, he helped negotiate the Peace of Prague with the Protestant states, especially Saxony in 1635.
Having been elected King of the Romans in 1636, he succeeded his father as Holy Roman Emperor in 1637. He hoped to be able to make peace soon with France and Sweden, but the war dragged on for another 11 years, finally coming to an end with the Peace of Westphalia (Treaty of Münster with France, Treaty of Osnabrück with Sweden) in 1648, both negotiated by his envoy Maximilian von und zu Trauttmansdorff, a diplomat who had been made a count in 1623 by his father Ferdinand II.