Bard, highly trained Celtic poet, composer, singer, and harpist who served as oral historian, political critic, eulogizer, and entertainer. The poems were passed from one bard to another orally, each adding some personal embroidery to the text; memorization was aided by the use of certain “formulas,” such as fixed phrases and repeated verses or groups of verses. The Celtic bardic tradition dates to ancient times but was most prominent in medieval and postmedieval Wales and Ireland. Many bards were resident in wealthy homes; others were itinerant. They were particularly important in Wales, where bards were often nobles, and where bardic guilds were formed to set standards for writing and reciting. Repeatedly outlawed by the English as politically inciting, the institution gradually died out. Some poetic texts survive, but little music remains. Professional musicians with similar functions have existed in many cultures; they include the Armenian gusan, the Yugoslavian guslari, and the aoidos of Homeric Greece.