"On February 27th, 1505, Queen Isabella quietly passed away in her sleep. Her health had been in decline for years, following numerous family tragedies, though it appears though the birth of her English Grandchildren boosted her health. Upon Isabella's passing, her eldest daughter, Joanna of Aragon, ascended the throne, as Queen Joanna I. Though Joanna and her husband Philip would hesitate to come to Castile. Joanna was pregnant with child and feared that she could suffer a miscarriage on the way to Castile. As such, Ferdinand II of Aragon would act as Regent of Castile until the two arrived in Castile."
- Gilles de Oviedo, "The Sun Shall Rise: The History of the Spanish Empire"
"In early 1504, Louis XII of France and Duchess Anne of Brittany agreed to betroth their eldest daughter, Claude of France, to Francis of Angouleme. This resulted in Louis breaking Claude's previous betrothal to Charles of Burgundy. Francis of Angouleme, was the heir to France, as the French followed Salic Law, which barred women from inheriting the throne. Brittany on the other hand, did not follow Salic Law. By betrothing the Francis to Claude, Louis had ensured Brittany wouldn't fall into foreign hands upon his death."
- Pierre de Montagu, "The Renaissance King: Francis I of France"
"In September of 1505, Queen Joanna of Castile finally gave birth, this time to a girl. The girl was named Mary, after her Paternal Grandmother and Maternal Aunt. Little Mary would be the only one of Joanna's children to be born an Infanta of Spain. Not long after Joanna and Philip finally departed for Spain. They left their heir, Charles behind with his siblings however, as the Burgundians refused to accept him as their heir if he were not raised there. During their journey to Spain, they would get caught up in a storm in the English Channel. Thankfully however both would arrive in Spain unharmed in March 1506."
- Gilles de Oviedo, "The Mad Queen: Joanna of Castile"
"Tragically for Joanna, Philip of Burgundy died not long after they were sworn in as Monarchs of Castile. It is believed Ferdinand II of Aragon poisoned him so that he could maintain control over Castile and because Ferdinand famously hated Philip. Joanna was devastated and mourned her husband, which led to her being deemed unfit to rule. This lead to Ferdinand becoming Regent of Castile, while Margaret of Austria, the sister of Philip, would serve as Regent of Burgundy."
- Post on HISTORY.Net, posted by anonymous user
"Not long after Joanna's ascension to the throne of Spain, Philip of Burgundy and Manuel of Portugal began discussing a potential betrothal between Crown Prince John of Portugal and Eleanor of Austria. These talks would later be continued between Manuel and Margaret, which later resulted in a betrothal between John and Eleanor being arranged in 1507."
Antonio de Enriquez, "The Aviz, Portugal's Greatest Dynasty"