The Kingdom of Saxony spearheaded the initial efforts to create a separate customs and commercial union, along with Saxe-Weimar-Eisenach and Saxe-Coburg.
They were supported in their efforts by the United Kingdom and the Empire of Austria, since they also wished to limit Prussian influence.
On 21 May 1828, the Kingdom of Hannover, the Electorate of Hesse, the Free City of Frankfurt, the Duchy of Nassau, Saxe-Coburg and Gotha, Saxe-Altenburg, and Schwarzburg-Rudolstadt decided not to join any other customs union within the following three years.
The pact could only be effective with a transit toll or trade barrier for goods going into the Prussian-Hessian zone.
Through enticements and pressure, the Prussians were successful in persuading some of the Central German union's members to leave.