The paper presents unknown compositions by a forgotten Polish composer, educator and organizer of musical life, active in the first half of the 20th century, in various centres in Poland and abroad. The main content is preceded by a biographical sketch, based on biographical notes in en- cyclopedias and lexicons. The works, most of which have not been published and which have been preserved in manuscripts, are discussed on the basis of the author’s own source research and two publisher’s commentaries. When dealing with the main subject, a descriptive method of analysis of a musical work has been applied, which focuses on the musical form, including the compositional technique and taking into account the specificity of violin playing and the expressive aspect. The presentation concerns 22 compositions by M. Popławski: Berceuse for violin and piano, 1906; Pre- lude. Etudes pour violon avec accomp. Piano, 1907; Prelude and dance “W górach” (en. “In the mountains”) for violin and piano, 1908; La fleur fanée for violin and piano, 1908, Passage for violin and piano, 1908; Sonata in F-sharp minor for violin and piano, 1908; Drei Skizzen for violin and piano, 1908: All Ongarese, Chansonete, Eroticon, Sonata in E minor for solo violin, 1911; Suite “W słońcu” (en. “In the sun”) for violin and piano, 1912; Variations „Za toboj Lizet” for violin and piano, 1913; Reverie for violin and piano, 1913; Valse for violin and harp, 1916; Menuetto for violin and harp, 1916; Mazurka for violin and harp, 1916; Rigaudon for violin and piano,1918; Polka for violin and piano, 1918; Etude for solo violin, 1918; Menuetto (ancient style) for violin and piano, 1920; Caprice for violin and piano, 1922; Air for violin and piano, without date. The analyses conducted allowed the following assertions regarding M. Popławski’s compositions: — the composer’s output comprises works of various genres (dance, lyrical, virtuoso, sonatas) and is classified as Neoromantic style; — the compositional technique is characterised by the principle of “permanent evolution” in the shaping of musical narration and makes use of intensive chromaticism; — later pieces tend to modernize the sound language; — the preserved Popławski’s works constitute the last stage of the late Romantic virtuoso style in Polish violin literature.