Leopold I (also Luitpold; c. 940 – 10 July 994), known as the Illustrious (German: der Erlauchte) was a member of the House of Babenberg who ruled as Margrave of Austria from 976 until his death.

While his ancestry remains disputed, a descent from the Popponids (Elder House of Babenberg) is assumed and some affiliation with the ducal Luitpoldings dynasty is probable.

[4] After Otto I had defeated the Magyars in the 955 Battle of Lechfeld, he re-established the Bavarian Marcha orientalis (Eastern March) in the conquered territories, placing them under the command of Margrave Burkhard,[1] a brother-in-law of Duchess Judith, consort of Duke Henry II of Bavaria.

Leopold's margraviate originally coincided with the present-day Wachau valley, and whose eastern boundary was the Traisen river near Sankt Pölten east of Krems.

[1] By 987, Leopold extended the boundary of his margraviate to the east as far as the Wienerwald mountain range[7] and by 991, jointly with reinstated Duke Henry II of Bavaria, further down to the Fischa river.

[11] Perhaps the highest testimony to Leopold's life and reputation came from the actions of Emperor Otto III, who immediately invested his son Henry I with his father's margravate.