Frederick (III) (born c. 1286—died Jan. 13, 1330, Gutenstein, Austria) was a German king from 1314 to 1326, also duke of Austria (as Frederick III) from 1308, the second son of the German king Albert I.
After his father’s murder (1308) Frederick became the head of the House of Habsburg and duke of Austria but did not succeed him as king, the count of Luxembourg being elected instead, as Henry VII. Frederick and his brothers made a treaty with Henry at Speyer in 1309, whereby they renounced the Habsburg claim to Bohemia in return for a sum of 50,000 Marks. Frederick’s quarrel with his cousin Louis IV of Upper Bavaria concerning the wardship of Henry III of Lower Bavaria ended with Frederick’s defeat at Gammelsdorf on Nov. 9, 1313.
Henry VII’s death (August 1313) led to a double election. Four electors chose Frederick as German king at Sachsenhausen, near Frankfurt, on Oct. 19, 1314, and he was crowned by the correct archbishop, namely the archbishop of Cologne, but at the wrong place, Bonn (instead of Aachen), on November 25. On the other hand, five electors chose Louis of Bavaria outside Frankfurt on October 20, and Louis was crowned at the correct place but by the wrong archbishop (Mainz) on November 25 likewise. The resultant war between the two rivals lasted nearly eight years. Finally, Frederick was decisively defeated by Louis on Sept. 28, 1322, at Mühldorf in Bavaria and was imprisoned in the castle of Trausnitz (Upper Palatinate). In March 1325 he was freed after taking an oath to recognize Louis as king and to see to it that his brother Leopold did so too. When he proved unable to do so he returned voluntarily to prison, though the Pope had freed him from his oath. In September 1325 Louis accepted Frederick as co-ruler, but after Leopold’s death (February 1326) Frederick’s power was confined to Austria.