*high spoiler level (books 6-)*
In The Wheel of Time
, an Aes Sedai
, supposedly a former member of Green Ajah
, currently an Amyrlin Seat
in Little Tower.
Egwene was born in Two Rivers, in Emond's Field as an innkeeper's daughter and was all but promised to marry Rand al'Thor one day. However, when Moiraine Damodred arrived and too Rand and pals away, Egwene followed. During her adventures it became apparent that she didn't actually love Rand and left him to three other women.
She also learned that she can channel, actually very strongly, being the second most powerful female channeler of her age, and went to training in White Tower. From there she was captured by the Seanchan and bound as damane, which has hardened her character and given her sometimes almost senseless hate toward Seanchan.
Again, also, she was found out to possess a Talent called Dreaming, which means she can enter Tel'aran'rhiod at will, and also be able to foretell the future in there. To learn control her dreamwalking skills, she went to the Aiel Waste where she was in training of Wise Ones. From there she wandered to Salidar where she was raised Aes Sedai (although it couldn't be *official*; they lacked an Oath Rod) and later, Amyrlin Seat. A reason for raising such a newbie was two-fold, first, she was strong (which was, as Siuan Sanche pointed out, important for a leading figure of a channeling society) in One Power and second, they expected her to be easy to control, sort of puppet in throne. This proved wrong however, and she has more or less seized control over Little Tower using an interesting hole in Tower Law. Now she is leading the Little Tower against Elaida a'Roihan and White Tower.
After realizing she didn't really love Rand, she has found another target (supposedly, at least, and with RJ in question, obviously): Gawyn Trakand.