Frick was born in Alsenz, Germany, the son of a teacher. He was educated in Munich and studied jurisprudence at Heidelberg, graduating in 1901. He joined the Bavarian civil service in 1903, working as a lawyer at the police headquarters in Munich. He was made a Bezirksamtassessor in 1907 and rose to the position of Regierungsassessor by 1917. He took part in the Beer Hall Putsch (November 1923), at which time he was director of the Munich kriminalpolizei. He was one of those arrested and imprisoned for the putsch, tried for treason in April 1924 he was given a suspended sentence of 15 months imprisonment and was dismissed from his police job. He joined the NSDAP in May 1924 and worked for an insurance company.
He was elected to the Reichstag in May 1924 and associated himself with the radical Gregor Strasser, he was Fraktionsfuhrer for the NSDAP from 1927. He was appointed minister of the Interior and of Education for Thuringia in 1930.
When Hitler came to power in 1933 Frick was promoted to Minister of the Interior and was responsible for drafting many of the laws that set up the Nazi regime. Initially he was head of all German police forces, a post he lost in 1936 to Heinrich Himmler. He was Minister without portfolio until August 1943 when he lost out in a power struggle with Himmler. He was then appointed to the ceremonial post of Protector of Bohemia and Moravia.
He was arrested and tried before the International Military Tribunal at Nuremberg. His role as Minister over the Enabling Act, the later Nuremberg Laws and as controller of German concentration camps led to his conviction for planning, initiating and waging wars of aggression, war crimes and crimes against humanity. He was sentenced to death on October 1, 1946 and was hanged two weeks later.