As displaced persons, Edmar and his two sisters, with parents Edvin and Marita Mednis, were permitted to emigrate to the United States in 1950.

[1] Mednis was trained as a chemical engineer, then worked as a stockbroker, but became best known as a chess author.

Mednis finished second in the 1955 World Junior Championship behind Boris Spassky (the two drew their game).

He played on the 1962 US team at the 15th Chess Olympiad and finished equal third in the 1961–62 U.S. Championship.

He played in the 1979 Interzonal tournament in Riga, his birthplace and finished 15th equal.