The Balduk were a race whose warriors had fearsome reputations.
Shortly after Worf's son Alexander Rozhenko came to live with him on the USS Enterprise-D in 2368, he remarked in his personal log that he would, "gladly fight ten armed Balduk warriors rather than face one small child." This was in response to Alexander stealing a small model Draco lizard from the biolab during a class field trip. (TNG: "New Ground")
According to the Star Trek: Star Charts, on page 63, the Balduk were from the Balduk system. This system's primary was an A-type star. The system was located in the Beta Quadrant.