Octopus was formed in Frankfurt/Main in 1973 with an original lineup of bassist Claus-Dieter Kniemeyer, guitarist Pit Hensel, vocalist Jennifer Hensel, keyboardist Werner Littau and drummer Dieter Becke. By the time they went into the studio to record their first album Becke had been replaced by Frank Eule who, in turn, was replaced by Seppl Niemeyer in October, 1977.

The first two albums, "The Boat of Thoughts" (1976) and "An Ocean of Rocks" (1977) are heavy in keyboard work by Littau (organ, Moog synthesizer, and Mellotron) and are often reminiscent of Camel, albeit with a bit more of a hard edge. The band's lyrics on the first three albums are entirely in English. The first two albums are generally considered to be Octopus' best work.

In September, 1978 Pit Hensel was replaced by Win Kowa (formerly of Streetmark) on guitar. In June, 1979 Octopus played for 60,000 at „Rock gegen Rechts“ in Frankfurt/Main. The band began a shift to a straight hard rock style with the album "Rubber Angel", released in January, 1980. Kowa and Jennifer Hensel left after that album and were briefly replaced by Doris Tangel and Alex Rodman. During the summer of 1980 Georg Klivinyi took over as guitarist and Michael Stein joined as lead vocalist, giving the band an entirely different commercial sound for their final album "Hart Am Rand" (1981). The band went through a further series of personnel changes before finally disbanding in May, 1983.