The battle at Yaowu Ridge lasted twelve days. The elite Luzhou troops who had submitted to Mengwu left three thousand corpses before the forward valley slopes of Yaowu Ridge, watching helplessly as more and more Liang army troops crossed the river on the ice.
Even if they could temporarily capture one or two positions and drive the Liang army back two to three hundred paces, these would immediately be lost again. Besides sending people to rush to Taiyuan Prefecture to request reinforcements, Tian Weiye had no good solutions to think of.
At this time, the mountains of Jin territory were all covered in vast snow.
Especially on the northern slopes of Wuwu Mountain and Li Mountain, the accumulated snow was over two chi thick, greatly slowing the speed at which reinforcements could assemble and advance south.
Although Mashou Stronghold was solid and dangerous, the space inside the stronghold was cramped with many wooden structures. The defending forces were blockaded inside the stronghold and unable to come out to counterattack. Seven or eight whirlwind catapults and even more spring-arm scorpion crossbows continuously hurled stone projectiles and fire oil jars into the stronghold, igniting and collapsing the buildings inside, leaving the defending forces nowhere to hide.
Ten days later, seeing that reinforcements had never been able to fight through Yaowu Ridge to provide relief, and especially after the granary in the stronghold had unfortunately been pierced through its roof by stone projectiles in the first two days and then ignited by fire oil jars, when the meager remaining provisions were exhausted, Commander Gu Yanling opened the stronghold gate from inside and surrendered.
Attacking Mashou Stronghold was only the first step of this northern expedition campaign, and also the first step for subsequent warfare to proceed smoothly.
Mashou Stronghold’s special geographical position guarding the southern entrance of Ziguan Pass determined that the first battle must be fought at Mashou Stronghold.
Furthermore, the Yu River ice-sealed period was only slightly over two months, but there were extremely many strongholds along Ziguan Pass, most of them solid and dangerous. The great army advancing north might even need to fight for one or two years before finally gaining a foothold on the east bank of the Fen River.
During this period, they absolutely had to ensure establishment of a stable material supply route between the northern and southern banks that would not be harassed by enemy naval forces upstream and downstream.
Even though the Luoyang navy held absolute superiority on the Yu River, if the enemy built many large ships on the upper reaches of the Yu River and used the rapid currents to quickly ram downstream, the iron-armored assault ships would have no choice but to retreat if they didn’t want to be capsized.
Last year, the Mongol army had built many ships within the Wei River and in Yan and Jin Provinces, clearly intending to use this tactic to resist their control of the middle Yu River waterway. In the future, they would certainly use this method to disrupt their ship transport between the northern and southern banks.
After capturing Mashou Stronghold, the next step was to stretch iron chains between Mashou Stronghold and Lingshang Stronghold on the southern bank to blockade the waterway.
With Great Liang’s current smelting and casting technology and scale, making iron chains of any length was not a problem, but to stably suspend the chains across the Yu River, and later even consider further constructing an iron chain pontoon bridge—the self-weight of the chains and the water flow impact they would bear after bridge construction were all difficult problems that needed to be overcome.
The actual length of the iron chains and iron chain pontoon bridge should be as short as possible.
Mashou Stronghold and Lingshang Stronghold were each built on protruding positions on the northern and southern banks. At this point, the waterway was narrowest, forming a gorge of less than one thousand three hundred paces. The waterway narrowed at the gorge mouth, and the water flow impact force on the west side of the gorge mouth was still slightly less than on the east side.
Weighing all factors comprehensively, this was also the most suitable place to build an iron chain pontoon bridge.
Li Chi and Lin Sheng’s two infantry combat brigades had also arrived at Lingshang at this time. After capturing Mashou Stronghold, they led their troops to join forces with Su Lie and Huo Li. Wen Bo personally rushed over to take command, following closely behind the Mongol army retreating in panic toward Yuanqu City, directly pursuing them toward Yuanqu City.
Although there were still six enemy strongholds south of Yuanqu City, their scale and garrison numbers were quite limited.
If they first conquered the six southern enemy strongholds one by one, they would inevitably waste a great deal of time south of Yuanqu.
By that time, Tian Weiye would certainly have already assembled large numbers of reinforcements from the northern front into Yuanqu City and positioned them to defend key strategic points near Yuanqu City. Then if they wanted to capture Yuanqu City, it would be a protracted war of attrition, and they might very likely return empty-handed.
At this time, Wen Bo ignored the six enemy strongholds south of Yuanqu. Besides ordering Chen Yuanchen to lead troops out of Li Mountain and Wuwu Mountain to tie down the defending forces in these strongholds, he was not worried about supply routes possibly being cut. He directly led the elite infantry combat brigades of Su Lie, Lin Sheng, Wen Yuan, Huo Li, and Li Chi, following closely behind Tian Weiye’s fleeing soldiers to press directly toward Yuanqu City.
Facing the swarming elite Liang troops, Tian Weiye could not abandon Yuanqu City, yet knowing full well how passive being trapped in Yuanqu City would be, he deployed his army before the city for battle.
Under Wen Bo’s command, Su Lie, Wen Yuan, Li Chi, Huo Li, and Lin Sheng were all brave commanders. Entering the Yuanqu Basin, their troops charged back and forth. Tian Weiye could not withstand them and was forced to retreat into the city.
Wen Bo deployed his forces before the city but did not rush to attack. Instead, he first divided his troops to enter two passes northeast and northwest of Yuanqu City.
These two passes were also the main routes for northern enemy forces to reinforce Yuanqu from the south. As long as they blockaded these two passages, they could methodically besiege Tian Weiye’s over ten thousand troops in Yuanqu City and slowly resolve the situation.
As for the six southern enemy strongholds, after He Liufeng and Han Bao’s two infantry combat brigades arrived, they could conquer them one by one and restore smooth grain routes with Luoyang on the southern bank—this would all be completely in time.
Although Zhao Mengji’s troops in Mengzhou could advance west through the riverside area on the southern slope of Wuwu Mountain to reach the southern entrance of Ziguan Pass, at this time the Yu River was frozen, and Han Donghu could directly send troops from Xingyang and Hulao Pass to enter the northern bank and cut off the western advance route of Mengzhou reinforcements.
Furthermore, they only needed to establish defenses in the riverside area on the southern slope of Wuwu Mountain before the Yu River froze.
This was Han Donghu’s responsibility leading the Xingyang army. Wen Bo did not need to worry excessively about it.
Great Liang had prepared for this battle for two years, considering all factors extremely thoroughly. The minimum objective of this battle was to capture Yuanqu City, which occupied a key strategic position in the middle section of Ziguan Pass.
Yuanqu City was built in the Yuanqu Basin between Li Mountain and Wuwu Mountain, with the core area having about twelve to thirteen li of depth. The city itself only occupied one corner of the basin.
Yuanqu City was also located in the mountain heartland between Li Mountain and Wuwu Mountain, the primary stronghold guarding the middle section of Ziguan Pass.
During the three to four decades of struggle between Liang and Jin, Jin forces had repeatedly relied on Yuanqu City to repel Liang army forces entering Ziguan Pass.
The terrain outside Yuanqu City had both flat and rugged areas. Overall, the south, east, and north sides were relatively flat, while the west side was built close against the mountain cliffs of the eastern foothills of Li Mountain, with rugged terrain.
Yuanqu City had only three gates on the east, south, and north sides.
Besides Su Lie and Huo Li leading troops to circle north of Yuanqu City to blockade the passes through which reinforcements could advance south from two directions, Wen Bo led the elite forces of Wen Yuan, Li Chi, and Lin Sheng to establish camps respectively south and west of the city.
When Yao Xishui and Lu Qingxia climbed from a Mongol-defended mountain stronghold in the northern foothills of Li Mountain over a precipitous mountain path to reach a peak on the west side of Yuanqu City, taking in the entire situation within the Yuanqu Basin spanning only over ten li, their hearts turned half cold.
Over twenty thousand reinforcements coming from Jiang County, Anyi, Quwo, and other places were blocked in the deep, long gorges north of Yuanqu by several thousand elite Liang troops plus large quantities of excellent war equipment like mounted crossbows, scorpion crossbows, and war chariots, unable to advance south to reinforce Yuanqu. Meanwhile, except for the side of Yuanqu City facing the mountain cliffs, the other three sides were already completely surrounded by nearly thirty thousand Liang troops.
Yao Xishui also found it hard to imagine how the Mongol army could break through the blockade of four-hundred-pace-range war crossbows over deep gorges and narrow valleys.
Even if they placed large shields and refined iron war chariots in front and charged to the Liang army’s front lines regardless of casualties, engaging in close formation combat with the heavily armored Liang officers and soldiers in the confined battlefield, the Mongol army would mostly be at a disadvantage.
Although six defensive strongholds were still distributed along the forty-li-long ravine south of Yuanqu City and seemingly had not fallen, the defending forces totaled less than three thousand and were surrounded by over ten thousand Liang troops—being devoured one by one was only a matter of time.
The Liang army had also established defenses in the area near the north bank of the Yu River on the southern slope of Wuwu Mountain, intercepting Zhao Mengji from sending troops from Mengzhou to attack the southern entrance of Ziguan Pass.
In Lingshang Gorge and the upstream direction, at this time a total of twelve iron chains as thick as arms were already suspended across the Yu River.
Although Tian Weiye led only over twelve thousand of his elite troops and might be able to defend Yuanqu City for quite a long time, the problem was that the Mongol army’s reinforcement routes to Yuanqu City had already been blockaded.
To lift the siege of Yuanqu, the only way was for Wang Yuankui and Wang Xiaoxian to lead their troops regardless of casualties to counterattack Huazhou, Tongguan, and the Lantian Pass defended by Kong Xirong’s forces, applying military pressure on the Liang army from these two directions to ultimately force them to withdraw from outside Yuanqu City.
This strategy was not thought up by Lu Qingxia, but was suggested by Tian Weiye himself when he sent a messenger from Yuanqu City to climb over the peaks and ridges of the northeastern foothills of Li Mountain to rush to Anyi to see Xiao Siqing.
To facilitate this, Xiao Yiqing did not go to Anyi to supervise the battle but directly rushed to Yongzhou to see Wang Yuankui.
Wusu Dashi’s edict had been issued. On one hand, reinforcements were being assembled in Yan, Lin, and other places to advance south, strengthening the intensity of attacks on Huazhou and Tongguan from the western flank. On the other hand, Xiao Yiqing personally urged Wang Yuankui and Wang Xiaoxian to send troops from Qizhou and Yongzhou as soon as possible.
It was already late in the first month of the sixth year of Taihe. The River-Huai region was about to completely thaw, so they temporarily could not count on the Eastern Liang army and Mengzhou forces to coordinate attacks on the eastern flank of Liang.
Originally, breaching the Yu River embankment to drain floods into the Ying was a brilliant strategy, but who would have thought that as times and circumstances changed, the flood zones formed along both banks of the Ying and Guo Rivers would now instead become a barrier for Liang’s eastern flank?
Yao Xishui couldn’t help wondering whether Wusu Dashi and Xiao Yiqing’s hearts held regrets, never having anticipated that Zhu Yu would abdicate to Han Qian on his deathbed, causing the two most critical missteps that led to their current passive position.
At this moment, Yao Xishui couldn’t help but think of her elder brother far away in Longyou. Last year, her lady had also sent people to Chengzhou, but the two emissaries had been beheaded for public display as soon as they arrived in Chengzhou, leaving their hearts still bitter…