While Reformed ideas and churches found ever-widening distribution during this period, reaching as far as England and Poland, Lutheranism also increased its dominance in the Holy Roman Empire. The Augsburg Interim of 1548, a settlement between Holy Roman emperor Charles V and Protestants resulting from the Schmalkaldic War, made some concessions to Protestants but forced those who wished to practice their religion legally to adopt practices which the Reformed found repugnant. Some isolated Reformed churches were able to hold on in Germany including a church in Emden led by Polish reformer Jan Łaski which became an important center for Protestant refugees from the Low Countries. London and a few other cities in England; Wesel, Aachen, and Frankfurt, Germany; and Geneva, Switzerland were also important cities for Reformed refugees from the Low Countries, northern France, and other areas of the Holy Roman Empire where they were not tolerated. "Stranger churches" were established in these cities for refugee Protestants.