August Meier was born on 8 October 1900 in Mainz, then located in the Grand Duchy of Hesse, within the German Empire. In 1933, he joined the National Socialist German Workers' Party (NSDAP). Starting in 1936, he led a section of the Sicherheitsdienst (SD) in Wiesbaden and also worked for the SD in Breslau.

During World War II, Meier held command positions within the Einsatzgruppen, the mobile extermination units operating behind the Eastern Front. On 5 September 1941, he was appointed commander of Einsatzkommando 5 within Einsatzgruppe C. Between 5 September 1941 and February 1942, approximately 10,000 Jews were murdered under his command in Kiev, Rivne, and Zhytomyr. From 5 July 1942 to November 1942, he led Einsatzkommando 4b. In Stalingrad, he contracted typhus and malaria. He was evacuated by plane, treated in several military hospitals, and recovered in May 1943.

He was then appointed commander of the Security Police and the SD in Limoges, succeeding Hans Nikolai Jessen. His headquarters was located at the Villa Tivoli, near the Champ de Juillet. From Limoges, his department exercised authority over several regions and collaborated with other German police services as well as with French collaborationist forces.

Meier's time in Limoges was marked by the repression of Resistance members and civilians in the region. On 26 March 1944, 26 men were executed in Brantôme. He also provided false information to the command of the 2nd SS Panzer Division Das Reich, claiming that Oradour-sur-Glane was "infested with terrorists." On 10 June 1944, the day of the Oradour-sur-Glane massacre, SOE agent Violette Szabo was captured near Salon-la-Tour. Meier interrogated her after her arrest.

After the war, Meier was extradited to France in 1949. In June 1949, the military court of Bordeaux sentenced him to twenty years of hard labor. He was released in 1956 for health reasons. In 1959, he was questioned about events in Ukraine, then arrested and transferred to Hohenasperg Prison, where he committed suicide in May 1960.