Ralph Vaughan Williams collected this version of the Gloucestershire wassail in the Inn at Pembridge, Herefordshire in July or August 1909 and it was subsequently published as the "Gloucestershire Wassail". Despite the Pembridge version being complete and presumably from a Gloucestershire singer, Vaughan Williams chose, when he published the song, to use words from versions collected by Cecil Sharp from William Bayliss of Buckland and Isaac Bennett of Little Sodbury. This version of the carol has become popular worldwide and is sung today by many singers and choirs.
It is included in The New Oxford Book of Carols (#155).
I learned this first from the recording of the Kingston Trio on their Last Month of the Year album.