The Nguyen Lords were a powerful feudal dynasty that ruled southern Vietnam from the 16th to the 18th centuries. They established their authority in the region of Dai Viet and played a significant role in the expansion and consolidation of territory, particularly in Central Vietnam. The Nguyen Lords were known for their administrative reforms and efforts to promote agriculture and trade. The dynasty was founded by Nguyen Hoang, who became the first lord in 1558. The Nguyen Lords often clashed with the Trinh Lords, who controlled northern Vietnam, leading to a long-standing rivalry. This period set the stage for the eventual rise of the Nguyen Dynasty, which unified Vietnam in the 19th century.