Trinh – Nguyen War

After Mac Dynasty was established, the Trinh clan mobilized a resistance against the Mac Dynasty. In 1592, the Trinh clan conquered Thang Long and King Le came back to the throne but the power belonged to the Trinh Lords. Meanwhile, in the South, the Nguyen Lords extended their land to the Mekong River Delta and carried out a resistance against the Trinh Lords. 

Source: https://vietnamtourism.com/