Changes that would see a dramatic shift in how battles were fought with troops and tactics.
It was the start of the Crusades that one would start to see the changes happen, Western Europe was finally ready to go on the offensive instead of the defensive, they were turning east wards to reclaim "holy land".
One of the different troops that would be used when the need came was the invention of the Knight, who would become a central element to the advancement of feudalism, With that the knight had to be able to maintain expensive equipment and a horse, and with that he would have to practice fighting and teach others how to fight as he got older. So to do that one would needed a great deal of wealth to so. They were supported by the work and labor of his people. This saw smaller groups pockets of land owners, Knights would own a parcel of land and give it out to their vassals, lords would have given land to their Knights and Kings would have given land to their lords. It was thanks to the Crusades that the "feudal warfare" was on the decline; it preoccupied the feudal armies of the different lords, and kings and had them focus on turning east wards to reclaim the "holy land".
Lastly one of the major reasons for the decline of “feudal warfare” was when rich nobles were allowed to pay for soldiers rather than to fight themselves. Life changed and Mercenaries were