In 1724, Holy Roman-German Emperor asked the imperial Postmaster Prince Anselm Franz von Thurn und Taxis to take up residence in Frankfurt am Main. Between 1731 and 1739, he had a castle built in Frankfurt. In 1748, the castle became the administrative seat of the imperial post office operated by the Thurn und Taxis family.
In the same year, the Prince of Thurn und Taxis moved to Regensburg. The Holy Roman-German Empire was dissolved in 1806. When Bavaria took control of its own postal system in 1810, the House of Thurn und Taxis negotiated a postal monopoly within the Deutscher Bund and Frankfurt am Main became its seat. In 1895, Prince Albert I von Thurn und Taxis sold the castle to the Reichspost.
The castle was damaged by several bombing raids during World War II. Between 2004 and 2009, it was reconstructed in an altered form. It adjoins the MyZeil shopping centre that was constructed on a site used for decades by the Deutsche Bundespost.