Original: UN Secretary-General After World War II, he served as Executive Secretary of the Preparatory Commission of the United Nations in August 1945, being appointed Acting United Nations Secretary-General from October 1945 to February 1946 until the appointment of the first Secretary-General Trygve Lie.
Simplified: UN Secretary-General After World War II, he served as Executive Secretary of the Preparatory Commission of the United Nations in August 1945. He was appointed Acting United Nations Secretary-General from October 1945 to February 1946 until the appointment of the first Secretary-General Trygve Lie.