Isabella And Ferdinand - Volumes 1 - 3: Jean PlaidyCastile For Isabella: The early life of Isabella of Castile. Isabella is seen as a young girl, within a few steps of the throne; first in the care of an ambitious but unbalanced mother and later, in the licentious court of her half brother Henry IV. Weak and influenced by his favourites, Henry married a frivolous and immoral Princess, whose illicit affair brought scandal and confusion to Castile with the birth of a child whose legitimacy was in doubt.