You have to be careful talking about feudalism being "phased out" as there is yet much controversy in the historical community as to whether feudalism ever really existed:

See further in https://www.reddit.com/r/AskHistorians/comments/2bs0rc/ama_feudalism_didnt_exist_the_social_political/

and in the relevant FAQ section:

https://www.reddit.com/r/AskHistorians/wiki/middleages#wiki_feudalism