Distressed by Father Nithard's policies in foreign affairs, Don Juan refused to command the Spanish army. When one of his friends was executed for plotting to assassinate Father Nithard, Don Juan fled to Catalonia.
Don Juan threatened Madrid with 500 soldiers, forcing Father Nithard to flee the city. Don Juan then demanded rational justice, tax decreases, and budget cutting. Don Juan was temporarily appeased but returned in
with 12,000 men and took control of the government. Charles II had just reached his majority but, suffering physical and mental disabilities, was unfit to rule. Don Juan therefore dominated the government. However, food shortages, his preoccupation with intrigues launched by Mariana, and continued Spanish decline undermined his popularity.