Linguistic unity began in Germany with the introduction by printers in Cologne, Mainz, Strassburg, Nuremberg and Augsburg who standardised on their own central dialect, which gradually became the accepted form of German (especially after Luther adopted it for his Bible), throughout everywhere from Schleswig-Holstein to the Alps, except in the Low Countries where local printers standardised on what became Dutch. Linguistic unification was a very slow process, and local dialects survived much better in the south than in the north, where Brandenburg-Prussia was much more effective in imposing the new standard (because it was so much better organised administratively and particularly through its use of "standard" German in its army in which all its male citizens had to serve). Also the Platt Deutsch of northern Germany was so different from the new standard, that northern Germans had to learn it almost as if it was a foreign language, and therefore made much more effort to speak "correctly." Of the southern dialects, Schwitzer Deutsch has proved the most enduring, despite (or because of?) its being further from the Central German norm than any other southern Dialect, even those of Austria. The standard written language came first and is now universal, even in Switzerland.