During the roughly fifteen years spent as a political prisoner in Vietnamese labor camps from 1960 to 1977, Nguyen Chi Thien composed hundreds of poems. Released following the fall of Saigon, Thien delivered a manuscript of these poems to the British Embassy in Hanoi. He was arrested at the gate and taken to Hoa Lo - the well known Hanoi Hilton Prison, where he spent six of an additional twelve years of imprisonment, often in solitary confinement. During this time, his collection of vivid poems, known as Hoa Dia-Nguc began to circulate in two Vietnamese editions, and eventually overseas. Some of the poems were set to music and popularized by Vietnamese folksinger, Pham Duy. In 1984, a bilingual edition of the poems, translated into English by Vietnamese literature scholar Huynh Sanh Thong, was published under the title Flowers from Hell by the Council on Southeast Asia Studies at Yale University. In 1985, while it was still unknown if he were alive or dead, Thien was awarded the International Poetry Prize in Rotterdam in absentia on the basis of this book. He was released from prison in 1991 and lived in Hanoi until 1995 when he emigrated to the United States. He became a U.S. citizen in 2004.