He was the second son of Nguyễn Kim. When his father was assassinated by a Mạc supporter, his brother-in-law Trịnh Kiểm took command of the Lê royalist army. Sometime after his older brother (Nguyễn Uông) died (believed to have been poisoned), Nguyễn Hoàng requested his brother in law, and was appointed to govern the southernmost province of Vietnam.
As the second son of Nguyễn Kim, when his father was killed by a Mạc supporter, Trịnh Kiếm took command of the Lê royalist army. Following the death of his older brother (Nguyễn Uông), who was believed to have been poisoned, Nguyễn Hoàng requested Trịnh Kiếm and was appointed to govern the southernmost province of Vietnam.