Leopold I was Duke of Austria and Styria for nearly three decades in the early 14th Century, sharing power with two of his brothers.

He was born in 1290. His father was the eventual Holy Roman Emperor Albert I, and his mother was Elizabeth of Carinthia. He was his parents' third-oldest son and had older brothers named Rudolf and Frederick. When Albert was named King of Germany in 1298, he installed Rudolf, then 16, as his co-ruler for the Austrian lands. Technically, Rudolf, Frederick, and Leopold shared the titles of Duke of Austria and Duke of Styria.

Rudolf died in 1307, and Frederick and Leopold ruled on together. Their father was assassinated the following year, and Leopold took strong action against his father's killers.

Leopold joined the German king King Henry VII on a campaign in Italy in 1311, helping put down a revolt in Milan. When Henry died three years later, Leopold did all he could to get his brother Frederick elected King of Germany. Those efforts were in vain, as Louis IV of Bavaria won the right to be King of the Romans.

Frederick didn't accept his defeat and went to war against Louis IV. Frederick and his younger brother Henry found themselves captured at the 1322 Battle of Mühldorf, and Leopold worked hard to get them released. Frederick and Louis eventually found common ground, in 1325. It was not long after that, on Feb. 28, 1326, that Leopold died, in Strassburg. He was 35.

Leopold had married Catherine of Savoy in 1315. They had two daughters, Catherine and Agnes, both of whom lived into adulthood.