Chapter 502: Cutting Off the Return Route

Greater and Lesser Bolor were what is now the area under Kashmiri control, located among mountains and valleys, stretching for thousands of miles. Lesser Bolor was in the north, while Greater Bolor was in the south. In the traditional geopolitical landscape, Lesser Bolor favored the Tang Dynasty, whereas Greater Bolor leaned toward Tubo.
Though both regions were surrounded by steep mountains, there were paths connecting them. The Sindhu River, originating from Xiangxiong in Tubo, flowed north for two thousand miles before turning west toward Bactria, then south into Sindh, and finally reaching the sea in Punjab.
The Sindhu River, which turned west into Bactria, became the boundary between Greater and Lesser Bolor and the first obstacle the Tang army had to overcome.
It was mid-January of the second year of Zhenzhi. Although the plains had begun to show signs of spring, the high-altitude plateau regions remained a world of ice and snow. The snow here never melted, but the Sindhu River, flowing at the bottom of the valley, was too swift to freeze, remaining ice-free year-round. The rapid currents made it impossible to cross by boat. Those unfamiliar with the terrain would have to take a detour of thousands of miles, crossing the river from Gandhara to Kashmir before entering Greater Bolor.
But the 7,000 Tang soldiers, guided by two scouts, reached the edge of the great gorge. In this section, the Sindhu River was called the Lion Spring River. The scouts knew of a path that led down to the valley bottom, where they could cross the rapid river using a rope bridge.
However, the rope bridge had been cut by the people of Lesser Bolor as early as the eighth year of Tianbao, to prevent the Tubo from using Greater Bolor to attack them again. Yet even without the rope bridge, local hunters could cross the treacherous currents.
The 7,000 Tang soldiers struggled down to the valley bottom along a path on the cliff, with their warhorses following. The valley bottom was shrouded in mist, with towering white waves and deafening roar of the rapids. The two scouts, who were local hunters, built a raft and drifted through a section of rapids about two li long and ten zhang wide. They had only a short time—about the duration of brewing tea. If the raft overturned, they would die; if they missed the timing and hit a large rock in the river, they too would perish.
But fate favored the Tang army, and the two scouts crossed the river safely. There, they found two large rocks and wrapped long ropes around them to build a rope bridge. In reality, they could only create a simple rope structure—true suspension bridges were beyond their capabilities.
Soon, more than 300 Tang soldiers climbed across to the other side using the ropes and began quickly constructing a suspension bridge. On the opposite side, another 300 soldiers also worked together to build the bridge.

If locals were to build the bridge, it would take at least a month, but thanks to the efforts of 500 skilled Tang army craftsmen, a bridge 30 zhang long and only one zhang wide was constructed in just three days. Planks were laid on it, and 7,000 Tang soldiers crossed the Shiquan River and set off toward Great Bolor.
…
The capital of Great Bolor was called Baliti, located on the west bank of the Shiquan River. It was a city built on high mountains, known as the City of High Mountains. The inhabitants of Great Bolor were scattered across various high mountains and valleys, but there were not many people in Baliti itself—only over 10,000. The city was also small, not even comparable to the smallest counties in the Central Plains. Under the sunlight of the snowy lands, it resembled a castle out of a dream.
Great Bolor first submitted to the Tang Dynasty. As early as the Kaiyuan era, it sent envoys to Chang’an three times to meet Emperor Li Longji. However, due to the long distance, the Tang court could not provide protection for Great Bolor, which eventually fell under the control of the Tibetans and became a vassal state. After the Battle of Lesser Bolor in the sixth year of the Tianbao era, the Tibetan army withdrew from Lesser Bolor but still controlled Great Bolor. This time, as the Tibetan army marched toward Tokharistan, it used Great Bolor as a route. In other words, Great Bolor was the most important bridge for the Tibetans to reach Tokharistan. Seizing Great Bolor meant cutting off the Tibetans’ path back.
The Tibetans also understood the importance of Great Bolor, so they left 5,000 troops stationed there. Although 5,000 troops were fewer than 7,000 Tang soldiers, the Tibetan army held advantageous terrain, had ample supplies, and enjoyed the advantages of fighting at high altitudes. The difference of 2,000 troops could not compensate for the Tang army’s disadvantage.
War sometimes relied on stratagems, but more often it came down to strength and morale. An Baozhen understood this as well. After crossing the Shiquan River, he received information from scouts about the actual number of Tibetan troops and ordered his Tang army to stop advancing and camp in a valley 120 li away from the capital.
At that time, Yaxin, the prime minister of Lesser Bolor who had come along, was brought before An Baozhen by soldiers. Yaxin was a middle-aged man in his fifties, the brother of Great Bolor’s king Ting Su, and in charge of Lesser Bolor’s government affairs. Since the Tang army’s campaign against Great Bolor was aimed not at Great Bolor’s own troops but at the Tibetan troops stationed there, winning the support of Great Bolor was a crucial guarantee for their victory.
Yaxin had lived in Chang’an for ten years in his youth and could speak fluent Chinese. He came before An Baozhen, bowed to him, and said, “Saluting General An!”

An Baozhen returned the bow and handed Ya Xin the letter written by Li Qingan to the king of Greater Bulei, saying earnestly, “I’ll have to trouble you now.”
“No problem. I’ll go persuade my brother to see reason, understand the bigger picture, and cooperate with the Tang army to save Greater Bulei’s fate.”
“I wonder how confident you are in persuading the king.”
Ya Xin thought for a moment before smiling and saying, “Originally, I was only 50% confident, but with Prince Zhao’s personal letter, I’m about 70% confident. I know my brother is also suffering under Tibetan oppression. If the Tang army has enough strength to drive the Tibetans away, he should be willing to cooperate with Anxi. I’m sure of it.”
“Then thank you! I’m counting on you.”
Ya Xin left the valley immediately, taking a few men with him to Barleti City to carry out An Baozhen’s orders.
…
Greater Bulei and Lesser Bulei were originally of the same clan and both belonged to the Bulei people. Decades ago, after Bulei was defeated by the Tibetans, it split into Greater and Lesser Bulei. Despite this division, the two countries had always maintained a close relationship. The queen of Lesser Bulei, Xue Lian, had even been betrothed to a prince of Greater Bulei. However, due to the Battle of Lesser Bulei in the sixth year of Tianbao, Lesser Bulei came under Tang control, while Greater Bulei remained under Tibetan control. This meant the two countries missed an opportunity to reunify. Although there had been no official exchanges for several years, civilian interactions continued unabated. Blood is thicker than water, and the two countries remained brotherly nations.
The king of Greater Bulei was named Ting Su, in his early fifties. He had ruled Greater Bulei for nearly thirty years, shifting from pro-Tang to pro-Tibetan stances. The changing political landscape had made him see through the power struggles between the two nations. Greater Bulei had few choices: if the Tang Dynasty was strong, they had to ally with it; if Tibet was powerful, they had to ally with them. Only in this way could Greater Bulei avoid destruction. It was a reluctant choice, but if Ting Su had to pick, he would prefer the Tang Dynasty. The reason was simple—the Tang Dynasty didn’t demand a single penny from them and even gave them generous gifts, whereas Tibet did. They had been paying a heavy tax of one-fifth of their income for over a decade. Tibetan exploitation and restrictions on trade kept the people of Greater Bulei in extreme poverty. Meanwhile, their brotherly nation of Lesser Bulei was much richer. Over the years, many people from Greater Bulei crossed the Shiquan River to seek livelihood in Lesser Bulei, causing Lesser Bulei, which was originally less prosperous, to surpass them greatly in terms of population and economic prosperity. This widening gap filled Ting Su with helplessness, as he had no solution. When under someone else’s roof, one has no choice but to bow one’s head.

Early that day, as soon as he got up, he felt a severe headache. He had a feeling that something might happen today. Just then, a servant reported that his brother Yaxin had arrived.
Tingsu was stunned. The brothers hadn’t seen each other in three years, and these days weren’t any special occasions—why had he come? After a moment’s thought, Tingsu guessed that his brother’s visit was likely related to the current situation. This matter couldn’t be known by the Tibetans, so he immediately ordered one of his confidants, “Take him in through the side door without anyone noticing.”
Soon after, Yaxin entered the room accompanied by two guards. After three years apart, the brothers embraced warmly upon meeting.
“Why have you come?” Tingsu asked, taking his brother’s hand and sitting down.
Yaxin smiled and asked tentatively, “I came specifically to see my elder brother and check if you’ve been doing well. I heard the Tibetan king passed by—did he bring any benefits to Great Baluh?”
“Benefits?”
Tingsu gave a bitter smile. “Apart from causing me endless troubles, I don’t see any benefits at all. Every time he comes, my treasury becomes empty.” With that, he sighed again, “The Tibetans are like locusts, eager to devour everything I have. The people hate me, the nobles resent me—but who understands my hardships?”
“Then has my elder brother never considered cooperating with the Tang army?” Yaxin asked further.
“Shh!”
Tingsu glanced outside, locked the door, and pulled his brother into the inner room before whispering, “Tell me the truth—why exactly have you come?”
“Of course, I’ve come to save you.”
With that, Yaxin took out a letter written by Li Qing’an in his own hand and handed it to his brother. “This is a personal letter from Prince Zhao, the governor of Anxi, addressed to you. Please read it yourself!”
Tingsu also knew Chinese. He read it carefully twice, then remained silent for a long time before suddenly asking, “Where are the Tang troops now?”
“Ten thousand Tang soldiers have crossed the Shiquan River. They are now less than two hundred li away. I came specifically to save you.”
Tingsu paced back and forth in the room with his hands behind his back. Some things didn’t need to be said—he fully understood Li Qing’an’s intentions, which he also knew well. But that wasn’t important. If Li Qing’an had no purpose, he wouldn’t have come looking for him. What concerned him was what outcome Li Qing’an’s intentions would bring him.
Tingsu still hesitated between Tibet and the Tang Dynasty. He was well aware of the cost of betraying Tibet—that his head would be hung on the highest tower of the castle. But returning to the Tang Dynasty meant Great Baluh would be completely freed from Tibetan domination.

Yaxin also noticed his brother’s concern and persuaded him, “The situation in Turfan is now quite clear. The Tang army will engage in a major battle with the Tubo army there. The reason the Tang army wants to attack Dabuli is obvious—they intend to cut off the Tubo army’s retreat and wipe them out entirely in Turfan.”
“But Tubo has an army of 180,000!”
This was exactly what Ting Su was most worried about. With 180,000 troops gathered in Turfan, it was an unprecedented force. Could the Tang army really compete with them?
“I think you’re overthinking it, brother. If the Tang army weren’t confident, they would have taken action last year when Tubo first occupied Turfan and hadn’t yet stabilized their position. Why wait until now? Brother, in the sixth year of Tianbao, Dabuli missed an opportunity. Now another chance has arisen, and you can’t afford to lose it again.”
His brother’s earnest persuasion finally convinced Ting Su, who was already inclined to act. Yes, they couldn’t afford to miss this chance anymore. With 10,000 Tang troops having crossed the river, the end of the Tubo army was near.
With a “bang!” he slammed his fist on the table and declared resolutely, “Alright! I’ll follow your advice.”
……
The Tubo army was stationed in two groups in Dabuli. One group of 2,000 troops was stationed on the east bank of the Shiquan River, while another group of 3,000 was on the west bank. This was because the Tubo had learned from the lessons of the sixth year of Tianbao. Back then, they had 200,000 troops on the east bank of the Boyi River, with no troops on the west bank, which allowed the Tang army to cut down the rope bridge and prevent them from crossing. This time, by stationing troops on both banks, the Tubo aimed to defend against a surprise attack by the Tang army. The Tubo commander in Dabuli was Lun Chadezan, a Tubo general of about forty years old. He was just an ordinary commander in the Tubo army with little fame. Moreover, Lun Chadezan was extremely fond of alcohol, spending at least eight out of twelve hours a day drunk. For this reason, he could only stay in Dabuli and couldn’t go to Turfan to fight.
The Tubo army’s camp was located five li east of Dabuli’s capital, Baliti City, in a strategically important small fortress that controlled the main route eastward. That noon, Dabuli’s king Ting Su sent someone to urgently inform Lun Chadezan that a Tang army patrol of about 400 men had been spotted fifty li north of Baliti City. The Dabuli army dared not go there, so they asked the Tubo army to eliminate this patrol.

Lun Chadezan had no doubts about Tingsudi sending the message; he also believed that the troops of Great Boli lacked the courage to confront the Tang army. How could they dare to fight against the Tang forces? Yet, four hundred Tang soldiers were neither too few nor too many, which indeed made Lun Chadezan think carefully. In the end, he led 1,500 men to eliminate this Tang patrol.

The massive Tibetan army rushed across the plateau at full speed. Their combat capabilities on the plateau were far superior to those on the plains. The thin air there had no effect on them, allowing them to travel long distances for extended periods without losing strength, even after running for two or three hours.

Dusk was approaching. By then, the Tibetan army had already spotted the Tang forces—a Tang patrol team appeared about ten miles away, fleeing northward. Eager to earn glory, Lun Chadezan ignored the darkening sky and immediately ordered, “Speed up the pursuit! We must catch up with the Tang army and wipe them out completely!”

The Tibetan soldiers quickened their pace. Five hundred cavalry and a thousand infantry formed a long black dragon, charging northward.

As night fell, a bright moon rose above the plateau. The sky resembled a pure black crystal, and the snow-capped peaks took on a dreamlike, shimmering glow under the moonlight.

At this moment, the 1,500 Tibetan soldiers passed through a gorge. The gorge wasn’t very high, but its sides were steep and vertical like cut by a knife, casting dim light inside.

The gorge was about five miles long. When the Tibetan army reached halfway, Lun Chadezan began to feel uneasy. The Tang army was known for their cunning tactics—could there be an ambush? But thinking that the Tang forces numbered only four hundred, even if there was an ambush, its destructive power wouldn’t be great.

He raised his wine flask and downed more than a dozen gulps of wine. The alcohol burned in his body, doubling his courage. On the plateau, it was the Tibetans’ domain—what were the Tang forces compared to that?

Just then, he seemed to hear a rumbling sound, like distant thunder, growing louder and louder. Not only him but all the Tibetan soldiers heard it. He looked around and suddenly saw dozens of huge, pitch-black shadows appearing before them at incredible speed, accompanied by a fierce wind, rushing toward them with a “whoosh!”

The Tibetan army was terrified. They could clearly see that each shadow was a boulder weighing over a thousand pounds. Before they could react, dozens of massive boulders crashed into their ranks. Instantly, screams filled the air, along with the crunching sound of bones breaking and the crushing noise of people being flattened into meat pies. In that instant, hundreds of Tibetan soldiers died on the spot.

Immediately afterward, dozens more boulders rolled down from the mountain tops on both sides. The Tibetan soldiers fled in panic, while Lun Chadezan was stunned into silence. He turned his horse around to escape, but a boulder struck the back leg of his horse. The warhorse let out a painful cry, fell to the ground, and threw Lun Chadezan more than ten steps away. He narrowly escaped death, and two soldiers quickly helped him up and rushed toward the valley entrance they had come from. Nearly a thousand Tibetan soldiers followed him in their flight, while another two hundred headed toward the other exit.

The sudden attack and the extremely unfavorable terrain left the Tibetan army at a loss. They couldn’t even see a trace of their enemy, but one thing was clear to everyone: if they didn’t escape the valley, it would be their death sentence.

Lun Chadezan was filled with rage. He suspected that Ting Su had deceived him. All he could think about now was escaping to skin that damned king and use his skin to make drums.

When they were less than a hundred steps away from the valley entrance, a clanging sound was heard, followed by a barrage of arrows from the entrance. Powerful crossbow arrows pierced through the Tibetan soldiers’ leather and chainmail armor as well as their wooden shields. Cries of pain erupted, and a large number of Tibetan soldiers fell instantly. This time, Lun Chadezan wasn’t so lucky—a arrow pierced his skull, killing him on the spot.

The Tibetan soldiers turned to flee, but hundreds more were shot down from behind by the Tang army’s crossbow arrows. In the end, about five to six hundred managed to escape the range and head toward the other exit. Thousands of Tang soldiers advanced steadily, like mountains in motion, step by step, pushing deeper into the valley.

On the other side of the valley entrance, over two hundred Tibetan soldiers also fell victim to an ambush. A cavalry force of more than a thousand Tang soldiers charged in, slashing with swords and spears. Heads rolled, corpses littered the ground, and cries of agony filled the valley. In just a short while, all of those two hundred soldiers were killed without exception…

A bloodless massacre took place in the valley. The Tibetan soldiers were slaughtered over and over again. The Tang army refused to accept surrender, killing every last one of them. An hour later, the valley fell silent, filled with the pungent smell of blood. The Tang army quickly cleared the battlefield. Soon after, a cavalry unit of about a thousand men, wearing Tibetan armor and carrying Tibetan flags, emerged from the valley and rushed toward Baliti City, the capital of Great Boli.