Dating as far back as the 1920s and based upon the poetry of Cuban poet José Marti, the song has a rather complex history (see here: https://en.wikipedia.org/wiki/Guantanamera ). This was the first record hit for The Sandpipers and features Robie Lester on background vocals and narration by producer Tommy LiPuma.
Pop Chart Peaks: Cash Box & Record World 7, Billboard 9
45 single issued on A&M 806 - Guantanamera (Marti-Angulo-Seeger) by The Sandpipers, arranged by Mort Garson, produced by Tommy LiPuma
THE 1966 HITS ARCHIVE - Here in one place, a comprehensive collection of ‘pop’ best-sellers and songs which made an impact that were either released or enjoyed a major chunk of their popularity within the calendar year 1966 (some were recorded in 1965)