Could someone explain the differences between bastard Feudalism and the system that preceded it? This period of history is not my area of expertise but I have been reading up on the Wars of the Roses and feel that this question is vital to my understanding.
Well bastard feudalism was different type of social relationship. It's important to keep in mind that both of these terms of modern constructs, and that social relationships were constantly in flux during the middle ages. So "pure feudalism" in 1000 and 1300 would be completely different, as would "feudalism" in France, England and Spain. Modern scholars tend to stay away from both of these terms, preferring to talk about specifics and use clearer terms like fief-holding in regards to what we would generally consider "normal" feudalism.
Bastard feudalism emerged in the 14th century as the English kings created large, professional contract armies rather than feudal levies (well, technically this process started in the 13th century and Edward I's wars used similar, less advanced and less successful system). These armies were lead by great noblemen. The king would create an army by contract various magnates to raise certain numbers of troops, who would then be gathered together and go to the continent. In, for example, a 10,000 man army, one could imagine 5-10 Earls, barons and later dukes being contracted to raise 1000-2000 men each. These noblemen would then contract captains who would raise individual companies of a few dozen to a few hundred men each. These men would all fight for pay rather obligation as in a typical "feudal" army. Their service was not based on land tenure. Nonetheless, these contracts were social relationships as well. Great lords would usually contract captains who were there retainers in and around their main power bases.
These developments went hand-in-hand with the breakdown of traditional feudal hierarchies. A great English lord would not exercise control over a region or province like, say a French prince who official "owned" , for example, Burgundy or Brittany. Instead, he would control a critical mass of estates in a given area. He would be given certain offices (sheriff, justice of the peace) in this region (could be a county, party of a county or even two counties) and create a network of retainers -- lesser barons and primarily knights and other gentlemen. These men would not owe formal homage to their lord. Instead, they would serve him for political power, pay and protection. They would be granted their own offices, given preferential marriages and often serve with their lord on the continent. It was a much more informal, malleable system -- bastard feudalism. It was also ever changing. Some areas (say, Lancashire) were ruled quite directly by the dominant lord, while others (Norfolk, Suffolk, Kent) saw competition among various lords and a much greater degree of power for the gentry.
This is all a gross simplification of a very complex set of political and social arrangements that was ever-changing and continued well beyond what we would consider the "Middle Ages" (obviously a modern construct as well, Medieval people never heard about the Middle Ages!), so let me know if you'd like anything cleared up.
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