Short form of names ending in -bert, from Germanic 'beraht' meaning bright or famous.
Bert is a short form with a remarkably broad set of parent names behind it: Albert, Herbert, Robert, Bertram, Egbert, Gilbert, and Hubert all shorten naturally to Bert, each carrying the Old High German element beraht, meaning "bright" or "famous." This brightness is built into the very syllable — crisp, direct, incapable of pretension. As a standalone name, Bert reached peak popularity in the late 19th and early 20th centuries, when clipped, confident single-syllable names were fashionable for men who worked with their hands and stood by their word.
The cultural archive of famous Berts is surprisingly rich and tonally consistent. Bert the chimney sweep in Mary Poppins (1964), played by Dick Van Dyke with infectious good humor, fixed a certain image of the name: resourceful, cheerful, loyal, working-class in the best sense. Bert and Ernie on Sesame Street — Bert the precise, slightly exasperated straight man to Ernie's chaos — deepened the association with grounded practicality.
Before them, Buster Keaton's real first name was Joseph Frank, but Bert was common enough in early Hollywood that it appeared on marquees regularly. The name also belonged to Bert Williams, the pioneering African American comedian and Ziegfeld Follies star, one of the most celebrated performers of his era. Bert fell out of mainstream fashion by the mid-20th century, replaced by longer forms and then by the trend toward surname-style and invented names.
But it retains a sturdy, unpretentious charm that has made it interesting again to parents tired of elaborate names. It sounds like someone who shows up, fixes things, and doesn't make a fuss about it — qualities that age well.