**Leopoldine Konstantin** (1886–1965) was an Austrian actress of remarkable stage presence and elegance. With a solid theatrical background, she became a prominent figure in German silent and sound cinema from the early 1900s, distinguishing herself through her intensity and sophistication.

Forced to flee Nazi Germany, her international career culminated in the role of Madame Sebastian, the sinister and glacial mother of Alex Sebastian (Claude Rains), in Alfred Hitchcock's masterpiece *Notorious* (1946). This was her only American film and the role for which she is universally recognized.

Konstantin excelled at portraying aristocratic, complex, and often ambiguous or authoritarian female figures, mastering roles that demanded a strong presence and subtle psychological depth, qualities that made her memorable despite a limited American filmography.