He attended the First Boys' Gymnasium in Vilnius, which was located in the Palace of Vilnius University. He studied at the private M. Treskinas Music School in Skapo Street. In 1908 he graduated from the St Petersburg Conservatoire (with honours). Returning to Vilnius, he taught at the Vilnius branch of the Imperial Russian Music Society's music school from 1908-1915. In 1909 he began to organise the first symphony orchestra of Vilnius. He gave concerts in the theatre, concert halls, Botanical and Bernardine Gardens. Galkauskas was the first in Lithuania to organise concerts with lectures and explanations. In 1914, he collaborated in the publication "Meno diena" (Meno diena) published by the Vilnius Art Society. . During the war (1915-1918), after the music school staff retreated to Moscow, K. Galkauskas continued to work at the music school. In 1918, when the school was closed, K. In 1919, he founded and conducted the State Symphony Orchestra in Vilnius.
K. Galkauskas taught at the Vytautas the Great Gymnasium in Vilnius, taught music and directed the choir at the A. S. Pushkin Russian Gymnasium from 1924 to 1933, and worked at the Vilnius Jewish Music Institute. In 1941-1944 he taught at the Vilnius Belarusian Gymnasium. From 1940 he taught at the Vilnius State Music School, from 1945-1949 at the Vilnius Conservatoire, and from 1949-1963 at the State Conservatoire of the Lithuanian SSR
K. Galkauskas composed symphonies, chamber, instrumental and vocal music. He composed the opera "Gypsies", the operetta "The Happy Prince", ballets for children, cantatas in memory of J. Basanavičius, M. K. Čiurlionis, S. Darius and Girėnas, suites for choir, songs, romances and piano pieces. He has harmonised Lithuanian, Russian, Belarusian, Polish and Jewish folk songs.
K. Galkauskas's "Pieces for Piano" (Vilnius, 1965), "Works for Piano" (Vilnius, 1976) have been published. Galkauskas also wrote poems. During the interwar years, their translations were published in "Vilniaus aide".
Although K. Galkauskas did not speak Lithuanian, but, as Rapolas Mackonis writes in his book of reminiscences "The Old Generation of Vilnietse", we can classify him as a representative of the "noble generation of old Vilnietse, who more or less took an active part in the struggles for the rights of the Lithuanian nation.
As the composer himself wrote, his entire life (apart from seven years (1901-1908) spent at the St Petersburg Conservatoire) passed in Lithuania. After graduating, he turned down offers of higher positions in Russia and returned to his hometown.
Several books have been published on the composer's personality and life: a biographical essay by Aldona Matulaityte (1901-1986), Konstantinas Galkauskas, and a book in Belarusian by Liavon Luckkevich and Halina Voicik, Канстаньцiн Галкоўскi. The latter emphasises Galkauskas's Belarusian origin, his links with the Belarusian intelligentsia and his contribution to the development of Belarusian music. The music is described in the "Encyclopaedia of Music", Antanas Rimvydas Čaplinskas' "Vilnius Remembrance Book", "Rusские в истории и культуре Литвы"
1918-1959 K. Galkauskas lived in Vilnius, Pylimo st. 20. The apartment was without amenities, cold, damp. In 1928, the composer played the organ in the nearby Reformed Church. In 1960 he moved to an apartment in a new house in what was then Karolio Poželaos Street (now A. Goštauto Street), where he lived until his death.
In 1967, a memorial plaque was placed in Vilnius on the house at 20 Pylimo St. (Senamiesciai district), where Galkauskas lived from 1918 to 1959.
