Reinhold entered politics in 1917 by joining the state assemblies of Saxony, the Volkskammer and the Landtag, as a member of the DDP.
During this time he heavily criticized then Reich Minister of Finance, Otto von Schlieben, for his "faulty revenue estimates" and instead suggested using a surplus and deficit.
During this time, he suggested using tax cuts to stimulate the economy, but that it relied on the Reichstag stopped voting on expenditures.
In the end, his suggestions were eliminated by interest groups and it causing budgetary difficulties and he restored to a strict limit on spending.
[5] His doctoral advisor for the thesis was the German historian Gerhard Seeliger, although he also received help from the academians Erich Brandenburg and Karl Weule.
[2] He travelled abroad following the completion of his thesis, but returned to Germany in 1913 to take over the newspaper Leipziger Tageblatt, which he sold to Ullstein Verlag in 1921 in order to devote himself to his political activities fully.
[8] During this time he also owned Europäische Revue, a conservative pro-European integration magazine that was very influental during the interwar period, which was published by Der Neue Geist.
[11] He was repeatedly re-elected until 1926,[12] but he left the assemblies on 9 February 1924 in order to focus full-time as being Minister of Finance of Saxony.
[4] He was appointed Reich Minister of Finance of Saxony on 6 April 1920 in the cabinet of Georg Gradnauer, a position he would hold until 13 December 1920.
[14] He also criticized the "faulty revenue estimates" of Otto von Schlieben and so the heavy tax load had led to a cut in production, and instead suggested using using the surplus and a deficit, a position shared by Hermann Höpker-Aschoff who was the Minister of Finance of Prussia.
[4] He also ran into trouble as he cast doubt that annuities that were supposed to be due to the United States under the Dawes plan would ever be able to be met.
[22] Subsequently, it was debated that the German slump a few years later was not caused by Reinhold, but the failure to follow up on his budget plan and a return to fiscal orthodoxy.
This came after frequent travel to the United States in 1927 and 1928, where he spoke about the Dawes Plan to the Institute of Policy at Williams College at round tables, alongside people like Carlo Sforza.