Alfred Plogar was born in Vienna as third child of Henrietta and Josef Polak, a music teacher and composer. His father inspired him to become a master of the piano. Polgar first worked as an apprentice to a piano maker but by the late 1890s he turned to writing.
As he became more proficient and acceptable he wrote critical articles and sketches for the theater. Most of them were published in the satiric periodical Simplicissimus. He also contributed to Montagblatt, Vienna, Die Schaubuehne, Berlin. Following World War I he wrote for Der Friede and Der Neue Tag newspapers. Polgar published Kleine Zeit, a pacifist, social criticism. His anti-war sketches were gathered in Schwartz auf Weiss (1928), and in the book Hinterland (1929). In 1922, under the pen-name Polgar, he entered the editorship of the liberal Jewish newspaper Wiener Allgemeine Zeitung. His co-workers there were the Jewish publicists Peter Altenberg, Stefan Grossmann and Felix Salten. Polgar, together with Altenberg, Egon Friedell, Karl Kraus and others established the so called Literatencafes Zentral and the renowned Griensteidl (coffee houses which served as permanent meeting places and platforms for literati and other intellectuals). Polgar, himself a patron, described Das Cafe Zentral as a worldview rather than a coffee-house. In 1925 he became theater critic for Die Weltbuehne and Das Tagebuch, Berlin, and the following year settled in Berlin. He signed a solidarity declaration for members of the opposition in SDS (Schutzverband Deutscher Schriftsteller) in 1931.
His literary and financial success in the German capital was disrupted in 1933 with the Nazional-Socialist rule. Although Polgar no longer considered himself a Jew he had to flee from Germany because of his Jewish background. He returned to Vienna where he contributed to exiled newspapers and periodicals, including the Die neue Weltbuehne and, under the pseudonym Archibald Douglas to Das Neue Tagebuch. A few hours before the Anschluss (the annexation of Austria by Nazi Germany) he fled to France via Switzerland. In Paris, together with the authors Franz Werfel and Joseph Roth, he signed a proclamation for Liga fuer das geistige Oesterreich (League for Intellectual Austria) and contributed to Oesterreichische Post. He was member of the Board of Central Union of Austrian Emigrees. In 1940, two days before the German troops entered Paris, he and his wife managed to escape through Marseilles to Spain, where they boarded a ship for New York. In the U.S., he received aid from the Emergency Rescue Committee. Polgar worked in California for Metro-Goldwyn-Mayer film company for one year after which he returned to New York. He contributed to newspapers: Aufbau, AAT and Panorama, Buenos Aires. In the spring of 1948 Polgar moved to Switzerland. Polgar’s sketches, essays (An den Rand geschrieben, 1922), Ja un nein (1926/7) and reviews are known for their stylistic clarity and clear purpose. He was a master of the so-called kleinen Form (small form). He also wrote novellas, comedies and cabaret texts. Notable among his works are the comedies Goethe (1910), Soldatenleben im Frieden (both with Friedell), Gestern und heute (1922), Handbuch des Kritikers (1937). His books were banned in Nazi Germany. Among his post World War II publications were Anderseits (1948), Standpunkte (1953), Im Lauf der Zeit (1954).
Polgar received the Award of the City of Vienna in 1951. He died in Zurich, Switzerland in 1955.