Emilio Jacinto was a key leader and writer in the Katipunan revolutionary movement in the Philippines in the late 1800s. He served as an adviser, secretary, and fiscal to Katipunan founder Andres Bonifacio. Jacinto authored the Kartilya ng Katipunan, which outlined the rules and principles of the secret revolutionary society. The Kartilya emphasized morality, civic duty, and fighting for Philippine independence from Spanish colonial rule. Though he died young from malaria at age 24, Jacinto played an important role in articulating the vision and values of the Katipunan movement.