The story of Judith beheading Holofernes comes from the Old Testament's Book of Judith.
Holofernes was a Babylonian general leading an army sent by Nebuchadnezzar against the Hebrews. Judith, a Hebrew widow, entered the enemy camp and seduced Holofernes. She got him drunk and killed him, taking his head back to the Hebrew camp and inspiring them to defeat the invading army.
Many artists have chosen to explore the theme in art and sculpture.