East Frisia in the seventeenth century looked tolerant from a distance and felt much less tolerant up close. Lutherans, Reformed Christians, Mennonites, and a small Jewish community all lived in the region, but each town had its own dominant confession, and Norden was firmly Lutheran. Letting the Reformed - the Calvinist tradition - build a church inside the walls would have meant tacit acknowledgement that they belonged there. Norden's town council declined. The Reformed minority found a workaround that medieval and early-modern minorities found everywhere in Europe: they crossed the legal boundary to build on someone else's land. The Count of Luetetsburg, himself Reformed, said yes.

Frederick William of Brandenburg - the Great Elector - was one of the most consequential figures in seventeenth-century Germany. He had rebuilt his shattered electorate after the Thirty Years' War and was busy securing trade routes and territories wherever he could. The Reformed Christians of East Frisia were his coreligionists. In 1684, his troops were already in Greetsiel to the west, where he had pressed a territorial claim. When the Reformed congregation appealed for protection against Norden's raids, he sent soldiers across to Bargebur. The church got finished. The Brandenburg presence faded. The little Reformed congregation has worshipped at the same site ever since.

For three centuries Bargebur was its own municipality - tiny, agricultural, attached to the Luetetsburg estate. The Bundesstrasse 72 ring road eventually passed along its southern edge, separating it from the Tidofelder Holz, a small forest in the next municipality over. Along the Fehn Canal a footpath called the Verschoenerungsweg - literally the 'beautification way' - threaded between fields. On old maps the place was sometimes called Bergum or Westekelbur. On 1 July 1972, in one of West Germany's many municipal mergers, Bargebur was incorporated into Norden, becoming an urban quarter of the same town whose Lutheran townsfolk had once refused it the right to exist.

The quarter today covers 0.65 square kilometres and houses roughly five hundred people. The streets and houses have been absorbed into Norden's continuous built-up area - cross a particular street and you have left Bargebur for Norden proper without noticing. The Evangelical-Reformed Bargebur Church still stands, the same building the Brandenburg soldiers protected, with its congregation continuing the tradition started in defiance four hundred years ago. A historic miller's house is used as a community meeting place. It is the kind of East Frisian place where the surface looks like any other quiet German residential neighbourhood and the foundations beneath turn out to be made of religious feud and seventeenth-century cavalry.