Pedro Calungsod was a 17th-century Filipino missionary and catechist who served alongside the Jesuit priest Diego Luis de San Vitores. Born in the Visayas region, he traveled to the Mariana Islands to assist in spreading Christianity among the indigenous Chamorro people. His missionary work involved teaching the faith and performing baptisms, often amidst the difficulties of the local terrain and frequent typhoons. In 1672, while attempting to baptize a child, Calungsod was killed during a confrontation with local leaders, resulting in his death as a martyr.