Hasaan Ibn Ali (born William Henry Langford, Jr.;[note 1] May 6, 1931 – 1980) was an American jazz pianist and composer.

Ibn Ali was strongly influenced by Elmo Hope, and his playing was rapid and intense, retaining a sense of rhythm even when his style became increasingly unconventional.

[2] Based in Philadelphia, Ibn Ali freelanced and acquired a reputation locally as "an original composer and theorist", in musicologist Lewis Porter's words.

[8] John Murph in JazzTimes described it in 2014: "Thoroughly modern with a whimsical rhythmic undertow and wayward melodic passages, it sounds like a new Jason Moran composition.

[7] Alan Sukoenig, in his liner notes to the album, wrote: "For a while it appeared that it was Hasaan Ibn Ali's destiny to be known – to those who had heard of him at all – as the extraordinary jazz pianist from Philadelphia who had never made a record.

[15] Pope believed that the recordings were not released by Atlantic because the label found out that the pianist had been imprisoned shortly after the sessions for drug offences.

[3] Ibn Ali's parents had been killed in a fire that destroyed their home at 2406 North Gratz Street on October 24 that year.

[4] A reviewer for The Glasgow Herald in 1965 commented on Ibn Ali's playing on the Atlantic album with Roach that "One's first reaction is astonishment at the blazing finger technique, [...] and the complete individuality of his harmonics [sic]".

[21] AllMusic reviewer Scott Yanow described Ibn Ali's playing on the album as "intense, somewhat virtuosic and rhythmic, yet often melodic in a quirky way".

"[23] Jazz critic Kenny Mathieson described Ibn Ali as "An Elmo Hope acolyte with a rhythmic quirkiness that had him compared with [Thelonious] Monk and [Herbie] Nichols".