Monoethnic theology

Christianity is an interesting phenomenon. The founding documents are Jewish and semitic, yet historically, Christianity has been dominant in Europe and, for a time, the Levant–before that was overrun by Muslims. As a result, the interpretation of Scripture has been predominantly European. 

This means Catholic and Orthodox dogmatic theology have an essentially ethnic stamp in a way that Protestant theology does not. Historically, Protestant theology has an incidental ethnic stamp because it was generally produced by British and European theologians, as well as their far-flung decedents. But in principle, Protestant theology must always be reducible to the founding documents. Indeed, that's the standing test of Protestant theology. 

By contrast, Catholic (and Orthodox) dogmatic theology represents an "authoritative" interpretation that enjoys a certain autonomy in relation to Scripture, as something over and above Scripture. Since Catholics reject sola Scriptura, Sacred Tradition mustn't be reducible to the message of Scripture. By definition, tradition contributes something extra. Something independent of what can be derived from Scripture alone. 

But in that event, Catholic theology is welded to the thought-world of Italians (primarily), as well as Spaniards,  Germans, and French (secondarily). Those are the countries most influential in the formulation of Catholic theology. And Eastern Orthodoxy has its counterparts. To convert to Catholicism, you must convert to the traditional ethnic thought-world that produced the dogmatic theology of Catholicism. You must operate within their culturebound conceptual categories. 

So Catholicism and Eastern Orthodoxy are fundamentally ethnic religions in a way that Protestantism is not. Indeed, these are nearly monoethnic, given the overwhelming dominance of a few historically and geographically related nationalities feeding into the official formulations. 

By contrast, the Protestant faith is essentially universal. The  explanans (interpretation) is distinct and separable from the explanandum (Scripture) insofar as the legitimation for the explanans must derive from the source documents. Any ethnic overlay that's not reducible to the source has no final warrant.