This is the second in Henley's Plantagenet trilogy (The Falcon and the Flower, The Dragon and the Jewel and The Marriage Prize). When King John died, his oldest son, though still young, became King Henry III. Henry had a brother, Richard of Cornwall, and a sister, Eleanor. This is the story of the three siblings, and particularly Princess Eleanor and her second husband, Simon de Montfort, the Earl of Leicester.
When she is nine, Eleanor is wed to William Marshal, 2nd Earl of Pembroke (the son of the great William Marshal and equally as honorable). Eleanor has loved and admired William her whole life. The fact he's 30 years her senior is not a negative for her. William does not take her as a wife in truth until she is 16, wanting to allow her innocence as long as proper. Meanwhile, King Henry takes as his queen an impoverished and ambitious French Provençal, also named Eleanor, who is jealous of the king's sister and thinks to diminish her. Others are plotting the demise of William Marshall for his influence with the king. On the night William would finally claim his bride, he suffers an attack and suddenly dies. Poison is suspected. Eleanor is devastated at his death, and in front of the clergy takes a vow of chastity and perpetual widowhood. A year later, the great War Lord, Simon de Montfort, enters her life. Once he sees her, he decides Eleanor is the woman he must have.
If you like to read books in date order, here is the Plantagenet trilogy followed by the other books she wrote about the same time in chronological order:
* The Falcon and the Flower - late 12th century/early 13th
* The Dragon and the Jewel - 13th century
* The Marriage Prize - 13th century
* The Raven and the Rose - 15th century
* The Hawk and the Dove - 16th century
* The Pirate and the Pagan - 17th century