After finishing secondary studies, he was involved in the Hungarian Democratic Youth League (Madisz) in his birthplace between 1946 and 1947.
Following that he joined police and soon became a member of the State Protection Authority (ÁVH).
Returning home, he became Deputy Head of the Ministry of Foreign Affairs' 2nd Territorial Department (1960–1963).
[1] He served as Envoy, then Ambassador to Sweden from 1963 to 1969, also accredited to Iceland (1963–1969) and Norway (1963–1967).
[1] Esztergályos was the head of the Hungarian contingent of the International Commission of Control and Supervision (ICCS) during the Vietnam War for a short time in 1973.