DruidSong is Celtic and "folk" music. Celtic songs are drawn primarily from the Irish and Scottish traditions. "Folk" music is the style of music popular during the folk revival in the 1960s, and includes such traditional folk music and songsfrom a variety of sources, including works by such artists as Peter, Paul and Mary, Tom Paxton, Pete Seeger, Woody Guthrie, and original songs.
The music ranges from the 13th through the 21st centuries. Some of the tunes may actually be far older than that, but that's as far as I've been able to trace them