What is the theme in The Lion in Winter by Anthony Harvey?

Another theme is political maneuvering. While the characters in The Lion in Winter are motivated by deeply personal feelings about each other, they are also engaged in real power struggles with vast political implications. The issue at hand concerns the outcome of three different questions: who will become the next king of England after Henry dies; who will marry Alais, the sister of the French king; and who will control the important French regions of the Vexin and the Aquitaine? The answer to each of these questions implies a reordering of the existing political power dynamics within the royal family and between France and England. All of the principle characters thus plot and counterplot with and against each other in order to determine the outcome of these three questions.