King Rilian was the son of legendary King Caspian X of Narnia and
Queen Lilliandil, fated to become king himself, and born in Narnian-year
2325. When Rilian was about twenty years old, his mother, Lilliandil
was attacked and killed while taking a nap in the northern lands, by a
giant green serpent. From then on he always returned to that place,
hoping to avenge his mother's death.
However, once up in these northern lands, Rilian became smitten
by the appearance of a beautiful woman, dressed in green. He did not
know who she was, but once he saw her, he forgot all about the serpent
and avenging his mother's death. Whether this was due to the woman's
beauty or some form of enchantment is unknown.