A person confined for decades could deteriorate.
A woman experiencing severe grief could behave differently after bereavement than before it.
Mental health itself can change across a lifetime.
And political descriptions of royal incapacity were never written in a vacuum.
This is why diagnosing Joanna from five centuries away is so hazardous.
Was She Really Insane?
There is no responsible way to give Joanna a definitive modern psychiatric diagnosis from the surviving historical record.
Various writers have proposed explanations ranging from severe depression to psychotic illness, but retrospective diagnosis is inherently uncertain.
What historians can examine more confidently is the political use of her reputation.
Philip sought greater control over Castile while Joanna was alive.
Ferdinand governed after Philip’s death.
Charles eventually exercised royal authority while his mother remained the lawful queen.
Every one of those arrangements became easier if Joanna was accepted as incapable of governing.
That does not prove that her illness was invented.
It proves that her illness was politically consequential.
And that distinction changes the story.
The question is not simply:
“Was Joanna mad?”
A more historically useful question is:
What evidence exists for her psychological condition, who described it, under what circumstances, and what did those descriptions allow other people to do?
Once the story is framed that way, the famous funeral procession looks different.
Joanna’s grief may have been intense.
Her behavior surrounding Philip’s corpse may indeed have alarmed observers.
Some extraordinary episodes may have happened.
But the lurid image of a crazed queen obsessively opening her husband’s coffin should not be treated uncritically as the explanation for everything that followed.
Joanna’s removal from power had political beneficiaries.
And her confinement lasted far beyond the immediate crisis created by Philip’s death.
Forty-Six Years Behind the Same Walls
The sheer duration of Joanna’s confinement is perhaps the most disturbing fact in the entire story.
She entered Tordesillas in 1509.
She remained there through Ferdinand’s death.
She remained there while her son Charles became one of the most powerful rulers in Europe.
She remained there through wars, rebellions and the upheavals of the Reformation.
She remained there as her children became kings, queens and imperial figures across Europe.
And she remained there until 1555.
Joanna died at Tordesillas in April of that year.