Philip IV of Spain was a king who ruled from 1621 to 1665. He was part of the Habsburg dynasty and is known for his efforts to maintain Spain's power during a time of decline. His reign saw the rise of influential artists like Diego Velázquez, who painted famous works such as "Las Meninas." Despite his patronage of the arts, Philip IV faced many challenges, including wars and economic troubles. His rule marked a period of political instability, and he struggled to manage the vast Spanish Empire, which included territories in Europe and the Americas.