Sandugo participant Datu Sikatuna
The Legazpi-Sikatuna Blood Compact or Sandugo (Spanish: Pacto de Sangre) was a blood compact, performed in the island of Bohol in the Philippines, between the Spanish explorer Miguel López de Legazpi and Datu Sikatuna the chieftain of Bohol on March 16, 1565, to seal their friendship as part of the tribal tradition. This is considered as the first treaty of friendship between the Spaniards and Filipinos. "Sandugo"  is a Visayan word which means "one blood".The Sandugo is depicted in both the provincial flag and the official seal of the government in Bohol. It also features the image of the blood compact. The top of the seal explains the history behind the Sandugo event that occurred in Bohol, the fleet and the location where the Spaniards anchored and the place where the treaty was conducted which was dated on March 16, 1565.Ceremony
The Sandugo began with the arrival of Miguel López de Legazpi in Bohol in 1565 and the establishment of allegiance by Datu Sikatuna to the king of Spain. They made a cut on their left arm with a dagger and poured their blood into a cup filled with wine, which they both drank in honour of their friendship. The inscription at a monument in Tagbilaran City describes the event:About the middle of March 1565, the fleet of Captain General Miguel López de Legazpi anchored along these shores. In the course of this visit, López de Legazpi entered into a blood compact with Datu Sikatuna for the purpose of insuring friendly relations between the Spaniards and Filipinos.
It added that the compact was performed as part of the tribal tradition.