Born the youngest daughter of King John of England in 1215, Eleanor was sister to the future King Henry, III, whose long and troublesome reign ( 1216-1272) spanned the greater part of the thirteenth century. The turbulent relationship between King Henry and his sister Eleanor would provide the backdrop to some of the most important political developments in England at the midpoint of the century.
When Henry III succeeded to the throne upon the death of his father in 1216, England was in the midst of a baronial revolt against the crown. Henry was but nine years old when he acceded. A regency was established, the Magna Carta, a charter guaranteeing justice issued in 1215, was reissued, and a measure of political unity was restored under the able leadership of dedicated servants of the Crown. In 1224, one of the king's chief vassals, William Marshal II, second Earl of Pembroke, negotiated a marriage contract with the monarch's counselors for the hand of the nine-year-old Eleanor. The king, who was still three years away from declaring himself of age to govern without his regency council, settled a dowry of ten manors and an income of £200 a year on his sister, but when her husband died suddenly in 1231, the sixteen-year-old widow was denied any portion of her husband's considerable estates in England, Wales, and Ireland. In particular, the Irish lands had been dowered to Eleanor, but William's older brother Richard claimed the inheritance and sold the widow's property in order to pay off her husband's debts. This action was in violation of the law that entitled widows to one third of their husband's estate. Although King Henry, as his sister's guardian, attempted to force compliance with the requirements of the law, Eleanor was never satisfied with the outcome, and her claims against her late husband's land became a lifelong enterprise. The episode revealed something of the young Eleanor's strong, and perhaps ava