Bach, Fugue in B Minor, Well-Tempered Clavier Book I, no. 24

Bach wrote two separate collections of contrapuntal works that contain preludes and fugues in each of the 24 major and minor keys. They are organized in pairs of parallel major/minor keys (C major and C minor, C♯ major and C♯ minor), ascending from C through B. This is the last fugue of Book I.