In the year 979, Đinh Tiên Hoàng and Crown Prince Đinh Liễn were assassinated. The nation, barely matured, had lost its King. The child ruler Đinh Toàn was only six years old, the court was in chaos, and the people's allegiance wavered. From the North, the Song dynasty heard the news and sneered:
"The Southern barbarians are without a ruler now is the time for the Northern Dragon to swallow the South!"
While the court was still debating, the wind of invasion had begun to blow at the borders. Lê Hoàn, then the Thập đạo tướng quân (Commander in Chief of Ten Circuits), the supreme commander of the Đại Cồ Việt army, was respected by his generals and loved by the people. In that moment of political vacuum, Empress Dowager Dương Vân Nga draped the royal robe over him, handing it directly to him in the great hall:
"If the nation falls, the people scatter; if the people scatter, the land and river cease to exist. I now entrust you with the Dragon Robe, so that you may protect the nation in my stead."
Lê Hoàn knelt down, his eyes shining like forged steel:
"If Heaven chooses me, I shall fight to let Heaven witness."
From that moment, a King was born from battle, and the Đại Cồ Việt land had a leader to bear the burden. In 981, the Song army crossed the border, their two armies by land and by water advancing into Giao Châu, led by the renowned general Hầu Nhân Bảo. The entire nation had only one choice fight. Lê Hoàn established his camp at Bạch Đằng, telling his generals:
"The enemy is numerous, but they possess only bodies. We are few, but we possess the Dragon and Fairy soul. If they use a thousand troops to fight, we shall use one heart to win!"
He then feigned surrender, luring the enemy deep into the estuary. When the tide receded, the iron tipped hardwood stakes appeared like the gaping jaws of a dragon. Drums shook the earth, and arrows burst like thunder in the sky. Hầu Nhân Bảo was slain, his blood staining the Bạch Đằng, and the Song warships sank like stars extinguishing in the river. The whole nation cheered:
"Đại Cồ Việt! The Southern Sky has its master!"
After the victory, the Celestial Song court sent an envoy to rebuke him. Lê Hoàn merely smiled, ordering his men to present the Song Emperor with a white rhinoceros a rare and precious animal found only in the South as an unspoken message:
"The Northerners may bring armies, but the Southerners bring diplomacy and principle. Do not test who is stronger, for Heaven has chosen the side that knows to bow before righteousness."
The Song Emperor was forced to accept the tribute, recording in their history:
"Giao Chỉ hữu dũng khả giao, bất khả xâm."
(Giao Chỉ is brave; we can engage in diplomacy, but we must not invade.)
Lê Đại Hành did not just fight invaders. He expanded the fields, opened mines, minted the "Thái Bình Hưng Bảo" coin, taught the people to cultivate rice, opened markets, and built pagodas.
"One hand holds the sword, the other plants the seed."
That was how he defended the nation, both with blood and with commitment. Towards the end of his life, he told his court officials:
"To defend the country is not just knowing how to fight, but knowing how to make the people believe this land is worth living for."
Lê Đại Hành passed away in 1005 the mountains and rivers were draped in white mourning cloth. On the Bạch Đằng River, the people released white lotus blossoms, each carrying an oath:
"The nation may be lost, but the will of the Việt people shall never be subdued."
And from then on, Đại Cồ Việt truly became a self governing nation, with authority equal to that of the Celestial Court's vassals. Later generations called him:
"The first King to make the North bow before the South."