Sedliar studied at the Kyiv Art School and, upon graduation, entered the Ukrainian State Academy of Arts. He worked in the state commissions’ workshop. In 1921, he began teaching at the Mezhyhirya Ceramic School-Studio. The students’ works from this school were exhibited in Prague, Berlin, Venice, Paris, and Moscow. Sedliar was passionate about Ukrainian icons, graphic art, carpets, goldsmithing, and theater. His students valued him for his profound intellect, broad cultural knowledge, and regarded him as a true mentor and companion.

Together with Oksana Pavlenko and Ivan Padalka, Sedliar revived ceramic production in Mezhyhirya and founded the Art-Ceramic Technical School and the Technological Institute of Ceramics and Glass.

In addition to teaching, Sedliar illustrated books, including works by Franko, Shkurupii, and Maiakovskyi. His illustrations for Taras Shevchenko’s Kobzar were particularly unique, resembling fresco painting, as noted by art historian Dmytro Horbachov. These works combined “the biblical quality of Shevchenko with the iconic style of Sedliar and other Boichuk followers”.

The authorities did not favor the Boichukists’ dedication to peasant and national themes, enforcing a uniform style that promoted false heroic pathos, triumph, and depictions of people’s happiness. Sedliar, a talented young artist, became a target of Stalinist repressions. Following the arrests of Ivan Padalka in September 1936 and Mykhailo Boichuk in November, Vasyl Sedliar was also arrested. Accused of “ideological sabotage,” as well as spying and participating in a counter-revolutionary organization, he was executed on July 13, 1937, along with Boichuk and Padalka.

All of Sedliar’s monumental works in Kyiv, Odesa, and Kharkiv were destroyed. Only imperfect photographic reproductions and a small collection of easel paintings and drawings remain. They preserved at the National Art Museum of Ukraine in Kyiv.