He was born in Budapest, then capital of the Kingdom of Hungary in the Austro-Hungarian Empire. His parents, Imre Békessy and Bianca Marton, were of Jewish origin but converted to the Christian faith. After World War I the family moved to Vienna where his father published one of the first daily tabloids, Die Stunde (The Hour), from 1923 to 1926. He was educated at the Franz-Joseph-Gymnasium between 1921 and 1929. Afterwards he started to study Law and German Literature at Heidelberg, but returned soon to Vienna because of the growing Anti-Semitism in Germany.

In 1930 he began to work as a reporter for the Wiener Sonn- und Montagspost (Vienna Sunday and Monday Post). Next year he became Editor of the Österreichische Abendzeitung (Austrian Evening News), at age 20 one of the youngest newspaper editors ever. At this time he married his first wife, Margit Bloch. Early in 1934 he moved to the Wiener Morgen (Vienna Morning News). From 1935 to 1939 he was a Foreign Correspondent for the Prager Tagblatt (Prague Daily News), stationed mostly at Geneva, covering the League of Nations. In this capacity he was present at the Evian Conference in 1938, where he met again otolaryngologist Heinrich Neumann von Héthárs who had performed an operation upon Habe 13 years before, and was a friend of his family. Habe described the course of the Conference in his novel The Mission (1965). The focal point of the novel is the infamous offer made by the German government, and transmitted to the Conference by Neumann von Héthárs, to sell the Austrian Jews to foreign countries at a price of $250 per capita, and the Conference delegates' refusal to accept. At this time Habe was married to his second wife, Erika Levy, the heiress of the Tungsram light bulb company.

After the Anschluss, Habe was expatriated and his books forbidden by the new Nazi government. He went into exile in France and joined the French Foreign Legion. In 1940 he was captured and interned in the Drancy camp. From there he managed to escape with the help of French friends and emigrated to the United States. He became a US citizen. Here Habe married his third wife, Eleanor Post Hutton, heiress of General Foods, in 1942. They had a son, Anthony Niklas Habe. In 1942 he was drafted into the US Army and studied Psychological warfare at the Military Intelligence Training Center at Camp Ritchie, Maryland. Then he joined the 1st Mobile Radio Broadcasting Company, and went in March 1943 to North Africa and participated in Operation Avalanche, the landing in Italy. In 1944 he became an Instructor of Psychological Warfare at Camp Sharpe, near Gettysburg, Pennsylvania. In autumn 1944 he selected a group of German writers and newspaperman to prepare for the publishing of new newspapers after the war in Germany.

In 1945 Habe returned to Germany in the wake of the occupying US Army. By November 1945 he had created 18 newspapers in the American Occupation Zone. Then he became Editor of the Neue Zeitung in Munich. At this time he was married for a short time with actress Ali Ghito. In 1949 he moved to the Münchner Illustrierte (Munich Illustrated), and in 1951 of the Echo der Woche (Echo of the Week). In 1948 he married his fifth wife, actress Eloise Hardt. In 1951 they had a daughter, Marina Elizabeth, who was murdered on 30 December 1968 in Los Angeles. 1952 and 1953 he wrote the column Outside America for the Los Angeles Daily News. When the Echo der Woche ceased to appear in 1953, he settled in Ascona and wrote mostly novels. 1954 he married his sixth and last wife, Hungarian actress and singer Licci Balla.