King John & Isabella of France

King John, Richard the Lionheart, Isabella of Gloucastor or 'childless'
King John  of England was the third king of the Plantagenet Dynasty. His brother Richard the Lionheart, died in battle, leaving no heirs for the throne. King John, who was in Wales at the time of Richard's death during a crusade, sprung into action. He seized the throne and proclaimed himself king.
King John was married to Isabella of Gloucastor, his 'childless' wife. King John decided to divorce her because of this. King John's second marriage was to another Isabella, this time to Isabella of France.
Isabella of France, Hugh X, and King Louis III
Isabella of France was 12 years old when she married 32 year old King John. They had a happy marriage, but there was just one problem-Isabella was already betrothed to Hugh X de Lusigine of France. Hugh was close to Isabella and loved her, so he complained to King Louis III of France. King Louis had been waiting for John to slip up. It was his time to complain to the Pope about John. Although, for awhile, Hugh and Louis had lost.
In the End...
Isabella and John had five children. Isabella later reunited with Hugh and had nine children after John had died of old age. John died 16 years after his marriage to Isabella. Married in 1200, died in 1216.

In the end it almost was like a love triangle. A mixed up weird one. Hugh X            King John
                                                                                                                 Isabella
Like that.