As MaxD said he was part of the international force sent to Russia in 1918/19 to support the "White Russians" against the Bolsheviks.
Commonly called Churchill's war it was a dismal & costly failure & most of the men returned home pretty much by the end of 1919.
My understanding is that no Medals were struck for this campaign, however if he was amongst the early arrivals there he may have qualified for the BW & V Medals as he was in a theatre of war.
It might help if you could give a close up of his medals so we can try & id them.