The song was written in 1967 and released in 1968 in England, where it failed to chart. The group had disbanded that year, but the song had great success the following year in the US, where it peaked at #3 in the charts.

Considered to be one of the classic psychedelic rock songs, it was part of one of the most well received albums of the era, Odessey and Oracle.

The song was notably sampled in Black Hippy’s “Rolling Stone,” as well as in Eminem’s “Rhyme Or Reason,” and Melanie Fiona’s “Give It To Me Right”.