The Battle of Cajamarca also spelled Cajamalca (though many contemporary scholars prefer to call it Massacre of Cajamarca) was the ambush and seizure of the Inca ruler Atahualpa by a small Spanish force led by Francisco Pizarro, on November 16, 1532. The Spanish killed thousands of Atahualpa's counselors, commanders, and unarmed attendants in the great plaza of Cajamarca, and caused his armed host outside the town to flee. The capture of Atahualpa marked the opening stage of the conquest of the pre-Columbian civilization of Peru.

Francisco Pizarro González (; Spanish: [fɾanˈθisko piˈθaro]; c. 16 March 1478 – 26 June 1541) was a Spanish conquistador, best known for his expeditions that led to the Spanish conquest of Peru.

Born in Trujillo, Spain to a poor family, Pizarro chose to pursue fortune and adventure in the New World. He went to the Gulf of Urabá, and accompanied Vasco Núñez de Balboa in his crossing of the Isthmus of Panama, where they became the first Europeans to reach the Pacific Ocean. He served as mayor of the newly founded Panama City for a few years and undertook two failed expeditions to Peru. In 1529, Pizarro obtained permission from the Spanish crown to lead a campaign to conquer Peru and went on his third, and successful, expedition.

When local people who lived along the coast resisted this invasion, Pizarro moved inland and founded the first Spanish settlement in Peru, San Miguel de Piura. After a series of manoeuvres, Pizarro captured the Incan emperor Atahualpa at the Battle of Cajamarca in November 1532. A ransom for the emperor's release was demanded and Atahualpa filled a room with gold, but Pizarro charged him with various crimes and executed him in July 1533. The same year, Pizarro entered the Inca capital of Cuzco and completed his conquest of Peru. In January 1535, Pizarro founded the city of Lima.