Eadgifu was one of three West Saxon sisters married to Continental kings: the others were Eadgyth, who married Otto I, Holy Roman Emperor and Eadhild, who married Hugh the Great. Eadgifu became the second wife of King Charles III of France, whom she married in 919 after the death of his first wife, Frederonne. Eadgifu was mother to Louis IV of France.
In 922 Charles III was deposed and the next year taken prisoner by Count Herbert II of Vermandois, an ally of the then current king. To protect her son's safety Eadgifu took him to England in 923 to the court of her half-brother, King Æthelstan of England. Because of this, Louis IV of France became known as Louis d'Outremer of France. He stayed there until 936, when he was called back to France to be crowned King. Eadgifu accompanied him.
She retired to a convent in Laon. In 951, Heribert the Old, Count of Omois, abducted and married her, to the great anger of her son (wikipedia.com)