Freiherr Sigismund Karl Johann von Reitzenstein (3 February 1766 in Nemmersdorf – 5 March 1847 in Karlsruhe) was the first minister of state of the Grand Duchy of Baden.

[1] From 1781, Reitzenstein studied law in Göttingen and Erlangen before getting a position in the Principality of Bayreuth.

[1] Reitzenstein did much to bring Baden closer to its powerful neighbor France.

During this period, not only did Baden become an Electorate, Reitzenstein oversaw the quadrupling of the size of the duchy.

In 1806 he returned to Paris to negotiate the marriage of Charles, Grand Duke of Baden to Napoleon's adopted daughter, Stéphanie de Beauharnais.