What year do some researchers say marked the point when Old Dutch morphed?
Old Dutch naturally evolved into Middle Dutch. The year 1150 is often cited as the time of the discontinuity, but it actually marks a time of profuse Dutch writing and during this period a rich Medieval Dutch literature developed. There was at that time no overarching standard language; Middle Dutch is rather a collective name for a number of closely related dialects whose ancestor was Old Dutch. But they were all mutually intelligible. In fact, since Dutch is a rather conservative language, the various literary works of that time today are often very readable for modern-day speakers.