Kingdom of Spain is actually a state of multiple kingdoms. It is composed of Castile, Aragon, Léon, Sicily and Naples. Most of the time it is owned by the Holy Roman Emperor. It has control over most of Southern America and has borders along OTL Texas border.
Kingdom of Spain became a reality on 23 January 1516, when Joanna I inherited Aragon from her father Ferdinand II of Aragon to add to Castile and Leon inherited 10 years earlier from her mother Isabella I of Castile, but she never called herself the Queen of Spain. In 1522 the entire spanish army went to help Pope Adrian VI and the future Charles I (then the Holy Roman Emperor). This was a disaster for Spain, the upkeep of the army caused a massive problem with money. Joanna had to be supported by her son for 3 years. In 1530 Spain changed its capital to Madrid and decided to take a course against the muslims, Joanna wanted to make sure that Spain would never again become Muslim and while Europeans were anoyed with the Lutherans, she took an army, crossed the Giblartar and crushed the Wattasid dynasty. Putting down her claim she created the Kingdom of Marocco and crowned herself in a ceremony on the most northern point of the state. Abu al-Abbas Ahmad ibn Muhammad (ruler of Wattasids) was very angry about this. Afterwards she turned to the affairs of the state and didn't do many other things. In 1557, Joanna's son became Charles I of Spain and his first order was a unification of the Holy Roman Empire and Spain. In 1558 angry people, mainly in the north east rebeled and stormed the main centers of bureaucracy, mainly in Madrid. In 1560 he crushed the revolt, but after that he never tried for a unification. Already stressed, Charles died in the City of Nice.
This part will be developed with his page.