In July-August 1937, he played second board at the 7th Chess Olympiad in Stockholm (+8 –5 =5)
In August-September 1939, he played second board at the 8th Chess Olympiad in Buenos Aires (+6 –8 =6)
His Olympiad total for Lithuania was (+36 -29 =18).
Vaitonis played three matches against Vladas Mikėnas. In 1934, he lost a match (2-6). In 1937, he lost (4.5-5.5) and in 1938 he lost (3-9).[4]
Vaitonis may have been the first player to use what is now called the Benko Gambit (1.d4 Nf6 2.c4 c5 3.d5 b5), in its most common move order, in a game against Einar Thorvaldsson at the 1936 Munich non-FIDE Olympiad.[5]
Vaitonis was Lithuanian champion in 1934, 1937, 1938, 1942, and 1944.[6] In July 1943, he took 4th place, behind Birmanas, Romanas Arlauskas, and Leonardas Abramavičius, at the 12th Lithuanian Championship in Vilnius.[7] He left Lithuania just before the advancing Soviet forces to avoid deportation to Siberia or other persecutions of the occupying Soviet regime (e.g., Vladimirs Petrovs). In 1944-45, he joined the exodus of many other Baltic players - such as Arlauskas, Dreibergs, Endzelins, Jursevskis, Mednis, Ozols, Sarapu, Tautvaišas, Zemgalis - to the West.
In 1948, he came to Canada and settled in Hamilton, Ontario. He wrote a weekly chess column for the Hamilton Spectator from 1953–55.
In 1949, Vaitonis took 5th place at the Canadian championship at Arvida, Quebec. In 1951 and again in 1957, he won the Canadian championship at Vancouver.[8][9] In September-October 1952, he took 19th place at the 2nd Interzonal at Stockholm.[10] In 1953, he took 3rd place at the Canadian championship at Winnipeg.[11]
