What was the accepted Halacha in the Franco-German Jewish communities of the early Middle Ages? Their custom was to allow eating dairy after meat as long as a disuniting action was performed in between. Some Ashkenazi rishonim required only kinuach ve’hadach; others required birkas hamazon. Rashi (as cited by Siddur Rashi and Manhig) and Rashbam required birkas hamazon – the dairy foods must be consumed in a separate meal. Rabbeinu Tam allowed their consumption in the same meal with an intermediary kinuach vehadacha. Consistency exists between the two Franco-German views – a time-waiting intermission as an absolute requirement was foreign to them.
R. Zerachiah HaLevi Baal Ha-Maor of Provence (c. 1125 – c. 1186) concurred independently with the view of R. Tam and reports that this was the general custom in France.
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The custom of the sages of France and Germany reflects the original Halacha and simplest reading of the Talmud. There were no Qaraite communities in France and Germany during that time period and, hence, the Franco-German sages saw no need to respond with a symbolic and social barrier. The existence of the original gaonic custom in European communities is in line with Haym Soloveitchik’s recent “Third Yeshiva of Bavel” hypothesis. Soloveitchik argues that the Ashkenazi scholarly community was transplanted from Iraq sometime between the years 930 and 960. This emigration occurred before R. Chananel’s new legislation. They, therefore, knew only the ancient Halacha and stuck with it because they had no reason to change.
Tzvi H. Adams, “Waiting Six Hours for Dairy – A Rabbanite Response to Qaraism”, Seforim Blog (11 August 2015) [http://seforim.blogspot.com/2015/08/waiting-six-hours-for-dairy-rabbanite.html]