[4][6] Fehrenbach started his political career in 1884 when he became a member of the Freiburg city council for the Catholic Centre Party.

He resigned his seat in 1887 after disagreements with the leader of the party in Baden, Theodor Wacker [de] over the dismantling of Otto von Bismarck's anti-Catholic Kulturkampf laws.

[5] As Chancellor, Fehrenbach had to deal with the communist-led revolt known as the March Action, which was put down with considerable loss of life by government troops, and with the Third Silesian Uprising of Polish insurgents.

In social policy, his government improved unemployment benefits, with the maximum amount for single males over the age of 21 increasing in November 1920 from 7 to 10 marks.

The total amount and the terms of reparations payments were also the subject of the conferences at Paris and London during the early months of 1921.

At the first London Conference in March, Fehrenbach and his foreign minister Walter Simons protested against what they saw as the exorbitantly high total reparations payments, which had not been finalized in the Versailles Treaty.

[9] In order to put pressure on Germany to accept the reparations terms, the Entente on 5 May issued the London ultimatum, which threatened an Allied occupation of the Ruhr if Germany did not comply with the London Schedule of Payments and the Treaty of Versailles' requirements for disarmament and the extradition of German "war criminals".

[6] In late 1923, Fehrenbach was elected head of the Centre Party contingent in the Reichstag, a position in which he remained until his death in 1926.

[6] Following the assassination of Foreign Minister Walther Rathenau, who was Jewish, by the ultra-nationalist paramilitary Organisation Consul on 24 June 1922, Fehrenbach became vice-chairman of the Association for Defence against Antisemitism (Verein zur Abwehr des Antisemitismus [de]).

He also supported the founding in 1924 of the Reichsbanner Schwarz-Rot-Gold, an unarmed, militarily structured joint organization of the SDP, DDP and Centre Party whose stated purpose was the non-violent protection of the republic from its enemies.