Did the Ajahs exist in the Age of Legends?
No, they were created a few hundred years in the aftermath of the Breaking.
BWB 9:
Almost nothing is known about the organization of Aes Sedai during the Age of Legends, but it is generally accepted that ajah played an important part, though apparently they were nothing like the present-day Ajah. In the surviving twenty-three consecutive pages of a dictionary from circa 50 AB, ajah , in the Old Tongue, is defined as “an informal and temporary group of people gathered together for a common purpose or goal, or by a common set of beliefs.” In thirty-one pages all in the same hand, located in the Royal Library in Cairhien, which appear to be random survivors of a larger manuscript reliably dated from the same period, the organization of Aes Sedai in the Age of Legends, or perhaps their manner of functioning, is described as “a vast sea of ajah (note: word deliberately left untranslated), all constantly shrinking, growing, dividing, combining, melting away only to be reborn in some new guise and begin the process once more.” In the first centuries after the Breaking, the nature of ajah or Ajah changed. We cannot be sure exactly when the change occurred, but another dictionary (circa 200 AB; 219 surviving random pages) defines Ajah as “a sisterhood of Aes Sedai,” and no lowercase form is listed.
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