Dagui was born in 1912 in the Ilocos province. His father was an officer in the national police of the Philippines. He lived with his uncle in Manila while attending high school as there were no high schools in his home area. During this period he became very lonely and was driven to write poetry to express his feelings, one of which was published in a national publication while he was still in high school. In 1932 he graduated with honors from the University of the Philippines. He returned to the area where he grew up and worked as a teacher and married a local woman. During WWII he joined the resistance and would eventually publish a well regarded collection of poems about his experiences during the war years. He is primarily known as a poet but also wrote some wonderful short stories.


In 1953 he received a Fulbright grant to study at Stanford University in California where he studied the short story. For Twenty Six years after returning from the USA he taught at the University of the East and the University of the Philippines. He passed away in 1966 and in 1973 he was awarded the National Cultural Award.