What forces were the mainstay of state power in Western European countries of the 17-18 centuries? Why?

Large feudal lords disappeared in European countries by the 17-18th century. The nobility at that time served for the good of the state, for their service they received land and salaries. Service for the nobles was considered an honor. The nobles also during this period had many privileges, which they did not want to give up. This was the reason that they supported the power of the one who was the ruler of the state, served as a support for him.