William Louis of Baden-Durlach (14 January 1732 – 17 December 1788) was the brother of the first Grand Duke of Baden, Charles Frederick.

After his father died in 1732 and his mother was suffering from a mental illness, his grandmother, Countess Magdalena Wilhelmine of Württemberg, took care of the education of William Louis and his brother Charles Frederick.

In 1745 and 1746 he traveled to Paris and the Netherlands, where he stayed with his uncle William IV of Orange, the later stadtholder of the Republic of the Seven United Provinces.

His uncle came to the conclusion that the undisciplined William Louis exerted a bad influence on his older brother, the Hereditary Prince Charles Frederick.

[3] William Louis bought land in Mühlburg and in 1769 he founded a dye plant, which was converted in 1770 into a Brewery and from 1771 also produced brandy.