The significance of the Spanish Armada in 1588 lies in its role in the decline of Spanish naval dominance and the shift of power in Europe. The Armada, a fleet sent by King Philip II of Spain to invade England and overthrow Queen Elizabeth I, was defeated by the English navy and adverse weather conditions. This loss marked a turning point, signaling the decline of Spain as the preeminent global power, while boosting English national pride and establishing England as a formidable naval force. The defeat influenced the power dynamics of Europe for years to come.