Essayist, journalist and commentator on international affairs. Unger spent his childhood and youth in Lwów (now Lviv, Ukraine), where his closest family were killed in the ghetto during the war. After 17 September 1939, when the Soviet Union invaded Poland from the east, he and his brother Leon managed to escape to Romania, where they remained throughout the war. Unger studied at the University of Bucharest, and for some time shared lodgings with Józef Beck and his family. (Beck was Poland's pre-war foreign minister.) After the war, for approximately a year, he edited Nowiny Polskie (Polish News) in the Romanian capital, then in 1948 became the Romanian correspondent of the Polish Press Agency (PAP). After his return to Poland in 1949, Unger lived in Warsaw and worked for Życie Warszawy (Warsaw Life). He decided to leave Poland after the government-incited anti-Semitic campaign of 1968. In 1969 he and his family moved to Brussels, where he was employed as a journalist by the Belgian daily newspaper Le Soir. Concurrently he undertook work for Radio Free Europe, the Polish Service of the BBC, and the International Herald Tribune. 

Unger was a regular contributor to Kultura from April 1970. Giedroyc entrusted him with a separate column entitled “Widziane z Brukseli” (As Seen from Brussels). Unger would sign his articles in the journal simply as Brukselczyk (The Man from Brussels). His work for Kultura primarily concerned international affairs and occasionally the Eastern Bloc. He received Kultura prizes twice, in 1977 and 1984. 

From the early 1990s Jerzy Unger also wrote for Warsaw’s Gazeta Wyborcza. 

Giedroyc’s Autobiografia na cztery ręce (Autobiography for Four Hands). was actually an edited transcript of his conversations with Leopold Unger, hence the title. In the book, Giedroyc noted that Unger “... wrote about both international and Polish matters. He did not replace Mieroszewski and never sought to do so. His contributions to Kultura, however, provided continuity in the field which the late Juliusz Mieroszewski had made his own. Without Unger this would not have been possible. Unger's writing was supremely competent and witty. It also had breadth and depth”.

In 2009, the Maria Curie-Skłodowska University in Lublin awarded Unger an honorary doctorate. 

For a select bibliography and other information, please refer to the notes at the end of the biographical note in Polish.