The history of the "Shulchan Aruch" is, in a way, identical with the history of rabbinical literature of the Jews in Poland for a period of two centuries. Recognition or denial of Karo's authority lay entirely with the Polish Talmudists. German Jewish authorities had been forced to give way to Polish ones as early as the beginning of the sixteenth century. Karo had already been opposed by several Sephardic contemporaries, Yom Tov Tzahalon, who designated the "Shulchan Aruch" as a book for "children and ignoramuses", and Jacob Castro, whose work "Erekh ha-Shulchan" consists of critical glosses to the "Shulchan Aruch". Moses Isserles and Maharshal were Karo's first important adversaries in Eastern Europe. Further in response to those who wished to force the rulings of the "Shulchan Aruch" upon those communities following Rambam, Karo wrote: