Blood compact

Blood compact (Spanish: Pacto de sangre, Filipino: Sanduguan) was an ancient ritual in the Philippines intended to seal a friendship or treaty, or to validate an agreement. The contracting parties would cut their wrists and pour their blood into a cup filled with liquid, such as wine, and drink the mixture.

A famous example of the blood compact was the 1565 Sandugo between Spanish explorer Miguel López de Legazpi and Datu Sikatuna, the chieftain of Bohol. Another blood compact was contracted between Portuguese explorer Ferdinand Magellan and Rajah Humabon of Cebu.

A similar ritual was practiced by initiates into the 19th century revolutionary group, the Katipunan. Though they did not consume their blood, they used it to sign their membership contracts.

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