I think that many of us only know of Fridrik Olafsson through other players (e.g. game 7 of Bobby Fischer’s My 60 Memorable Games) and not as a great in his own right. But he was - and this despite being largely an amateur. Have a look at this fine tribute to Olafsson - Grandmaster, Candidate, FIDE President, lawyer, and more - on the occasion of his 90th birthday.
[N.B. More players should be feted in this way, i.e., before they pass.]