In 1131 Alfonso the Battler, King of Aragon and Navarre, wrote a will that insisted his kingdom be given to the Knights Templer, Knights Hospitaler, and Knights of the Holy Sepulchre. When he died three years later, the nobles of the country refused to carry out these orders and made his brother Ramiro king.
Is there any way to get the Kingdom of Aragon into the hands of those three knightly orders? The Teutonic and Livonian orders both ruled large states. What are the effects on the Crusades? On the Templar's ultimate fate?
Very, very, very hard.
By making a slightly exageration, it's like a president of US proposed to give the leadership of the country to Blackwater. The king was a bit senile when he made the testament, admittedly.
Of course, many nobles were purely and simply pissed about it and prefered to use following arguments.
Alfons recieved
Aragon, Navarra, Sobrabe and Ribagorca by inheritance. He couldn't give them to someone that don't have such familial ties, and critically randomly to a moral person.
Furthermore, as said, the testament gave the Kingdom into pareage, to resume it's sharing it without dividing it by splitting the benefits.
The issue is, pareage doesn't work that well between too open rivals, the war in Provence between Tolosa, Aragon and Provencals show it.
At term, it could have meant the division of the Kingdom, and no noble was ready to allow that, critically with still powerful Moors in the south.
Even without regarding the capacities of projection of these orders in Spain, any tentative to enforce a claim on this would result on immediate revolt.
