Analysis of political regionalism and regionalist parties has traditionally neglected the case of Germany. We argue that this is a curious ommission. This article looks to redress this balance by applying frameworks created for understanding the determinants of regionalist party success to the Bavarian Christian Social Union (CSU) and the eastern Germany Party of Democratic Socialism (1990–2005, PDS). Although very different in terms of their politics, both parties have been successful as they have followed strategies and tactics evident in the broader regionalist parties' literature. This article therefore deepens our knowledge of regionalism in Germany, while also testing regionalist literatures in a new country-context.