For years, Isabella navigated her husband’s turbulent court and his conflicts with the aristocracy. She was not simply a passive figure trapped on the sidelines. As she matured, she became increasingly involved in politics and diplomacy.
But during the ascendancy of the Despensers, her position deteriorated dramatically.
By 1324, according to English Heritage, Hugh Despenser’s growing power was connected to measures that struck directly at Isabella’s independence: her properties were confiscated, and she was separated from her children and French attendants.
That rupture matters enormously in understanding what followed.
The story of Isabella’s rebellion is sometimes compressed into a sensational formula: an unhappy queen found a lover and returned with him to overthrow her husband.
The reality was more complicated.
By the mid-1320s, Isabella’s marriage was entangled in a wider political crisis involving royal favoritism, confiscated lands, rebellious nobles, Anglo-French tensions and the extraordinary dominance of the Despensers.
And Despenser had made enemies far beyond Isabella.
One surviving example illustrates how aggressively the family could pursue property. After Elizabeth Comyn inherited Goodrich Castle while still a minor, the Despensers pressured her to surrender possessions to them. English Heritage records that she was kidnapped and held prisoner until she relinquished Goodrich to Hugh Despenser the Younger in 1325.
This was the political world in which Isabella eventually turned against her husband.
Her opportunity came through France.
The Queen Who Refused to Come Home
Relations between England and France had deteriorated, creating a diplomatic problem involving Edward’s French possessions.
In 1325, Isabella traveled to France on a diplomatic mission.
That journey gave her something she had not possessed while surrounded by Edward and Despenser’s power in England: distance.
Her son Edward later joined her.
And Isabella did not simply return obediently to her husband’s court.
While abroad, she became allied with Roger Mortimer.
Mortimer was no ordinary exile. He was a powerful Marcher lord who had participated in rebellion against Edward II and the Despensers. After being imprisoned in the Tower of London, he escaped and made his way to the Continent.
Exactly when Isabella and Mortimer became lovers cannot be established with absolute precision. English Heritage states that Isabella “probably began a relationship” with Mortimer during her time in France and that by the following year they were widely believed to be lovers.
Whatever the private nature of their relationship, their political alliance became unmistakable.
They were now united against Edward II and Hugh Despenser.
And in 1326, they moved from opposition to invasion.
For a medieval queen to participate in armed action against her own husband was extraordinary. Kingship was surrounded by religious as well as political authority, and Isabella was not merely challenging one royal policy. The campaign threatened the king’s government itself.
Yet when Isabella and Mortimer landed in England in September, Edward discovered how isolated his regime had become.
Support gathered around the invaders.
The speed of the collapse exposed the weakness beneath the surface of Edward’s authority.
Within roughly three months, Edward II and Hugh Despenser had been captured.
For Despenser, there would be no recovery.
He was subjected to a brutal public execution at Hereford in November 1326.
For Edward, the consequences were more constitutionally complicated.