Before the dikes were built, the Vietnamese people were hunters and gathers of wild fruits in some areas such as Phu Tho, Hoa Binh, and Thanh Hoa provinces. As the time passed by, they discovered how to raise animals and sticky rice. When the population increased, the Vietnamese people moved down to the plains of the Red River Delta where they could grow rice. More land was opened up for rice cultivation to feed the expanding population. The construction of dikes along rivers is the most important part of the Vietnamese agriculture. Farmers saw the dikes as a matter of life and death because without dikes, the rice could not grow.
Ly Thanh Tong dedicated much of his energy to the advancement of learning. More schools were opened, and examinations