The Battle of Alcácer Quibir took place on August 4, 1578, in Morocco. It was a significant conflict between the forces of the Portuguese King Sebastião I and the Moroccan Sultan Abdel Malek. The battle was part of a larger struggle for control over North Africa and aimed to expand Portuguese influence in the region. The Portuguese army, numbering around 20,000, faced a much larger Moroccan force. Despite initial successes, the Portuguese were ultimately defeated, leading to the death of King Sebastião and a power vacuum in Portugal. This defeat significantly impacted Portuguese history and contributed to the eventual dynastic crisis in the country.