Liszt’s posthumous Piano Concerto in E-flat major was unknown until 1989, when the first edition of the score appeared. Coming soon after the discovery of De profundis, a further revelation was that, in addition to the well-known Piano Concertos in E flat major and A major, Liszt also composed another concerto, the author’s manuscript of which is divided into three parts and can be found in three different archives. Both works, which emerged from Liszt’s estate, were discovered and reconstructed by Jay Rosenblatt, an American Liszt scholar, based on the manuscripts. After studying the autograph, it could be ascertained that the posthumous piano concerto in E flat major was composed in 1839 and was intended for Liszt's first concert tour starting that same year (though he never played it), similar to the versions of the E flat major and the A major piano concertos of that time.

Liszt composed a mature concerto from heterogeneous elements of three juvenile piano pieces (Huit variations op. 1, Allegro di bravura, op. 4[a], and Rondo di bravura, op. 4[b]). The entire concerto can also be analysed as a single sonata form movement, with an exposition, development, and recapitulation in two keys (E minor and G-flat major), sections which also correspond to each movement. This dual construction principle, known as the „two-functional form” or „two-dimensional sonata form”, is what Liszt adopted, essentially already in 1835╩36 in De profundis, and in 1839 in the three concertos. These works can therefore be considered as the first mature realization of this Lisztian concept.