Why did Spain enter a period of decline after the death of Philip II?

Spain entered a period of decline after the death of Philip II in 1598 due to several interconnected factors. The Spanish Empire faced economic troubles, including heavy debt and inflation exacerbated by costly wars and the loss of profitable territories. Additionally, the weakening of central authority and increasing internal conflicts diminished Spain's political stability. This combination of economic strain and political fragmentation led to the gradual decline of Spain's power and influence in Europe.