Multiple choice The first Secretary General of the United Nations was Dag Hammarskjoeld Trygve Lie U. Thant Dr. Kurt Waldheim Reveal answer Fill a bubble to check yourself B Correct answer Explanation Trygve Lie, a Norwegian politician, served as the first Secretary General of the United Nations from 1946 to 1952. Dag Hammarskjoeld was the second, U Thant was the third, and Kurt Waldheim was the fourth.