Absolutism was a very common form of government in Europe between the 16th and 19th centuries and defended the theory of the king's absolute power over the entire nation. The power of kings during the Middle Ages was considered limited compared to the absolutist period, as there was a lot of political fragmentation and the king's influence depended on a relationship of vassalage, in which the exchange of favors between kings and nobles guaranteed real power.
As modern nations were being structured, mainly England, France and Spain, and as trade resurfaced in Europe, a new social class emerged with great economic power: the bourgeoisie. For the bourgeoisie, the political and economic fragmentation that existed since the Middle Ages was not interesting, as it affected their business, mainly because of the differences in currency and taxes existing from one province to another (even in provinces of the same kingdom, there were these differences in currency and taxes).
The nobility, in turn, welcomed the concentration of power in the figure of the monarch as a way to guarantee control of the lands he owned. Thus, the concentration of power in the hands of the king was a demand from the rising bourgeoisie and also from the nobility.
