After teaching English for a while and working in a Harlem settlement house, Merton decided (1941) to become a monk, choosing the Trappist order for its discipline of silence and solitude. Within the monastery he served for years as master of students and novices. Outside it, his writing, which included poetry, meditations, and works of social criticism, brought him prominence in American letters.
His autobiography, The Seven Storey Mountain (1948), became a bestseller. Merton's social criticisms burned deeply into public awareness of racism, economic injustice, and militarism. He was a vocal and controversial critic of the War in Vietnam.
Seeing parallels between Oriental mysticism and Western tradition, Merton gained permission to attend an ecumenical conference of Buddhist and Christian monks held in Bangkok, Thailand. While attending that meeting, he was accidentally electrocuted.