Eloy is a German progressive rock band, whose musical style includes symphonic and space rock, the latter theme being more prevalent on earlier albums. Founded in 1969 by guitarist Frank Bornemann, the band has endured several line-up changes, with Bornemann being the only consistent member of the group. In the 1980s, after a series of major splits in the group, Bornemann pursued a more commercial direction. Despite attracting a large following in Germany, the band never gained popularity in the United States. However, in later years, former members of the band re-joined, and in 1998 released the album Ocean 2, a return to the classic symphonic progressive rock genre for which the band was well known. In 2009, after numerous compilations, reissues, and box sets, Eloy reconvened for a new studio album. The resulting Visionary featured a lineup that included Frank Bornemann on lead vocals and guitar, Klaus-Peter Matziol on bass, Michael Gerlach on keyboards, and Bodo Schopf on drums and percussion. In 2017, after another long hiatus, the band released The Vision, the Sword and the Pyre, Pt. 1, the first of a planned two-volume rock opera about the life of Joan of Arc. The Vision, the Sword and the Pyre, Pt. 2 followed in late 2019.

Despite their nationality and time period, the band is not generally considered krautrock because of their sound, which has much more in common with English progressive rock groups such as Pink Floyd, King Crimson and Yes.