Riehl, a lawyer and former Social Democrat, was one of Austria's leading Nazi politicians in the 1920s. He joined us in 1909 in the German Workers' Party ( DAP). After the splitting of the successor states of the Austro-Hungarian monarchy Riehl took over in 1919 the presidency of the German National Socialist Workers' Party ( DNSAP ) in of the reorganized Republic of Austria. In August 1920, the creation of an agreed 'Intergovernmental firm ", combined with that by which the Nazi sister parties in Austria, Poland, Czechoslovakia, and now the party was founded in the German Reich and also the Nazi movement should be strengthened as a whole. Riehl was entrusted with the management of this firm and at the same time thus became "leaders " of all Nazi parties.
With the takeover of the Presidency of the National Socialist German Workers' Party ( NSDAP) in Munich by Adolf Hitler in 1921, there was a gradual deterioration of the previously good relationship between the Austrian and the German Nazi leadership. Hitler claimed the sole leadership of all Nazi parties and began more and more to Austrian affairs to interfere. This involved his growing conflict within the DNSAP the inflamed mainly on the question whether the party entered the essentially democratic parliamentary course for which Riehl, or the revolutionary extra-parliamentary course Hitler should control. The decision was made in August 1923 for the purposes of Hitler at a party congress in Salzburg. Riehl now put back his position as chairman of the DNSAP and founded the German Social Association. This should remain politically completely meaningless, but in 1924 Riehl's expulsion from the DNSAP meant. Riehl later became involved with the Combatants Association of German Austria. In 1930 he became a member of the NSDAP, but emerged no longer politically. His successor in the DNSAP was the foreman Charles Schulz.