Alexander Nikolayevich Scriabin (sometimes transliterated as Skriabin, Skryabin, or Scriabine) (6 January 1872–27 April 1915) was a Russian composer and pianist who developed a highly lyrical and idiosyncratic tonal language. Driven by a poetic, philosophical and aesthetic vision that bordered on the mystical, he can be considered the primary figure of Russian Symbolism in music.

from an article by the Eurasian Vegetarian Society in Moscow:

In April 1913 in Moscow there took place the 1st All-Russia Vegetarian Congress. Vegetarianism was widely spread in the country. Among vegetarians were the writers Bunin and Leskov, the composer Skryabin, the painter Levitan, the scientist Rerikh, the academician Nesmeyanov and other famous people. The famous Russian wrestler Ivan Poddubny also followed the vegetarian diet.

[referring to the creation of the new post-soviet vegetaian society] On December 11, 1989 the volunteers, who thought that the vegetarian society establishment will show people the way to healthy and moral life, will help to solve the problems of nutrition based on new principles, assembled in Scriabin museum hall. [the Scriabin museum is the house where Scriabin lived in Moscow.]

from several sources:

He embraced Helen Blavatsky’s Theosophy. In London he visited the room in which Mme. Blavatsky died.

- theosophists were usually vegetarian.

Scriabin was also embracing Wagner and Schopenhauer in 1890s, both of which would also have pointed him towards vegetarianism.

• A great Russian tone-poet, Scriabin (PDF 20mb) by A.E. Hull, London 1916. Refers to Scriabin's theosophy, from about 1904, which led to his vegetarianism.