[4] A native of Minsk, Belarus, his formal accordion studies began at the local Glinka State Musical College, where his teacher was Miron Boula.
While he was a student, from 1996 to 2001, Sevastian joined the Russian Radio Orchestra in Moscow, and with the support of the conductor Nikolai Nekrasov he became a featured soloist touring throughout Russia, Ukraine, Germany, Italy, and Japan.
From 2002 until 2018, as a member of the mixed instrument classical crossover ensemble Quartetto Gelato, Sevastian recorded five CDs, and toured every province in Canada, almost every state in the US, and many countries around the world including Russia, Korea and Mexico, The Bahamas, and Guatemala.
He later performed as soloist with the Calgary Philharmonic Orchestra as well with other orchestras in Canada including Victoria, Quebec City, Kelowna, Kamloops, Windsor, Edmonton, Mississauga, Nanaimo, as well as Charleston and Sioux City in the U.S.A. After winning the Coupe Mondiale International Accordion Competition in 2007, his fourth major competition win, his solo recital career blossomed.
He toured extensively, performing often at prestigious music festivals in Canada, and in Russia, Belarus, Ukraine, Germany, Japan, Mexico, Italy, Portugal, Serbia, and the US.
[7] Before his death, he had begun playing with Toronto's Payadora Tango Ensemble and was also acting as a promoter, bringing in musicians from Russia including Bayan Mix.