Charles ensured his domination and throne by having his mother confined for the rest of her life in the now demolished Royal Palace in Tordesillas, Castile.
Joanna's condition degenerated further.
She apparently became convinced that some of the nuns that took care of her wanted to kill her, a fear which was never proved.
Reportedly it was difficult for her to eat, sleep, bathe, or change her clothes.
Charles wrote to her caretakers: "It seems to me that the best and most suitable thing for you to do is to make sure that no person speaks with Her Majesty, for no good could come from it".

Joanna had her youngest daughter, Catherine of Austria, with her during Ferdinand II's time as regent, 1507–1516.
Her older daughter, Eleanor of Austria, had created a semblance of a household within the palace rooms.
In her final years, Joanna's physical state began to decline rapidly, with mobility ever more difficult.

Joanna died on Good Friday, 12 April 1555, at the age of 75 in the Royal Palace at Tordesillas.
She is entombed in the Royal Chapel of Granada (la Capilla Real) in Spain, alongside her parents, Isabella I and Ferdinand II, her husband Philip I and her nephew Miguel da Paz, Prince of Asturias.
Charles ensured his domination and throne by having his mother confined for the rest of her life in the now demolished Royal Palace in Tordesillas, Castile. Joanna's condition degenerated further. She apparently became convinced that some of the nuns that took care of her wanted to kill her, a fear which was never proved. Reportedly it was difficult for her to eat, sleep, bathe, or change her clothes. Charles wrote to her caretakers: "It seems to me that the best and most suitable thing for you to do is to make sure that no person speaks with Her Majesty, for no good could come from it".
Joanna had her youngest daughter, Catherine of Austria, with her during Ferdinand II's time as regent, 1507–1516. Her older daughter, Eleanor of Austria, had created a semblance of a household within the palace rooms. In her final years, Joanna's physical state began to decline rapidly, with mobility ever more difficult.
Joanna died on Good Friday, 12 April 1555, at the age of 75 in the Royal Palace at Tordesillas. She is entombed in the Royal Chapel of Granada (la Capilla Real) in Spain, alongside her parents, Isabella I and Ferdinand II, her husband Philip I and her nephew Miguel da Paz, Prince of Asturias.
Joanna of Castile