When the Eastern Han Dynasty was still strong, the Bingzhou under its control was very different from the Bingzhou in the Wei and Jin Dynasties.

Simply put, Bingzhou in the Eastern Han Dynasty included most of today's Shanxi Province, the northern half of Shaanxi Province (called Shangjun in the Eastern Han Dynasty, including today's Yan'an, Yulin and other places) and part of Inner Mongolia (called Shuofang, Wuyuan, Yunzhong counties in the Eastern Han Dynasty, including today's Baotou, Bayannur, Ordos, Hohhot and other places). In the Eastern Han Dynasty, except for the mainland of Shanxi Province, most of the other places were mixed with Han and Huns. (So some documents say that Lu Bu, who was born in Wuyuan County, had the ancestry of the Huns)

In the Wei and Jin dynasties, on the one hand, the Chinese country fell into a civil war, the national strength declined, and its control over border areas became rapidly weaker. On the other hand, the grassland people moved south and occupied a lot of Bingzhou's inherent land. The Southern Xiongnu, who were originally grazing on these lands, were unable to resist... Therefore, Bingzhou in the Wei and Jin dynasties was basically the same as the modern Shanxi Province.

The two large parts that were dismembered, the northern Shaanxi part, were mainly dominated by the Qiang people in this era, and there were many Xianbei people here, and the Huns also retained a certain territory. Therefore, when historians marked this territory during this period, they used the four words "Qianghu Mixed Houses". The essence of Inner Mongolia was all occupied by the Xianbei people.

Because Hetao is too plump and strategic location is too important, Guan Yi sent Wen Yang to recover Hetao shortly after taking over Guanzhong. Therefore, Ji Han now had an enclave in the northwest of Bingzhou in the Eastern Han Dynasty: Wuyuan County. Jiang Wei's departure base is here.

As for Shangjun, which links Chang'an and Wuyuan County, Ji Han did not have the ability to restore it at this time. He just ran through Shangjun and built a straight road. Guan Da Sima did not make too many requests to the many tribes grazing on this land: you sell the wool to us and help me keep the straight road smooth and safe. For other things, you can do whatever you want.

Walk east from Shangjun and cross the Yellow River, and it is Xihe County. This is the base camp after the Xiongnu moved south. The Xiongnu Chanyuting was set up here. Walking east from Xihe, it is the core county of Bingzhou: Taiyuan County.

To the north of Taiyuan County is Yanmen County. However, at this time, Yanmen County in Jin State was much smaller than Yanmen County in the Eastern Han Dynasty. At least the areas north of the Great Wall were basically occupied by the Xianbei people.

To the south of Taiyuan County is Shangdang County (a city dominated by high-ranking officials in Shanxi). The southern gate of Bingzhou, Huguan, and the current Dongdaemen Jingxing Pass (Nantius Pass was only available at the end of the Sui Dynasty and the early Tang Dynasty). They are all in Shangdang County. The core of the so-called victory in Bingzhou is actually Shangdang County. Only by taking over Shangdang County can we truly have a geographical advantage overlooking the Central Plains.

However, according to the traditional route of advance, if Guan Yi wants to enter Bingzhou for the 150,000, he actually does not go to Shangjun and cross the Yellow River to enter Bingzhou. Instead, he crosses the river in Pubanjin, Fengyi County, first enter Hedong County, Sizhou, and then goes north to enter Bingzhou.

The reason why we have to march on this route is of course determined by Shanxi's special geographical environment.

Shanxi, the mountains and rivers on the outside, inside and outside. On the west side, it is divided by the Yellow River and Shaanxi Province. Crossing the Yellow River from northern Shaanxi, while entering Shanxi Province, it also enters a mountain in the north and south directions: Luliang Mountain.

The east side of Shanxi: Taihang Mountain. The north side of Shanxi: Wutai Mountain and Heng Mountain. The south side of Shanxi: Zhongtiao Mountain and Wangwu Mountain. It can be said that the entire Shanxi Province is surrounded by mountains on all sides, just like Sichuan.

However, although there are many hills inside the Sichuan Basin, there are basically no mountains, and there are many plains in the basin. Inside this province surrounded by mountains, there are also areas such as Yizhoushan, Taiyueshan, Yunzhongshan and some of the Loess Plateau that have been scattered. The entire Shanxi Province is not an integral large basin like Sichuan. Instead, due to various mountainous situations, the plateau is divided into six larger basins and more than ten small basins. These six basins are the essence of ancient Shanxi.

As Guan Yi started from Chang'an, he wanted to march into Bingzhou and take over the core of Shangdang County, a place with great success in the world. The best route is: go north from Chang'an, go to Pubanjin, and enter Hedong County in Sizhou, Jinguo. This place is in the Yuncheng Basin, which is modern in Shanxi Province. Not only is the terrain flat, but it can also use Laishui, which flows east-west, to facilitate the transportation of military rations and other logistics supplies.

After taking over Hedong County, the Han army could continue to march northeast: the northeast of Yuncheng Basin is the Linfen Basin. The terrain is also very flat, and there are also big rivers like the Fen River to help it transport troops and food. After taking over here, in the north, along the Fen River north, the Taiyuan Basin is the Fen River and the river valleys along the coast, and it is very comfortable to march. To the east, although there is a large area of ​​the Loess Plateau, there is no huge mountain barrier - crossing this plateau, it is the Changzhi Basin - this era was called Shangdang County.

In short, this is basically the process of expeditioning Bingzhou from west to east. After taking over Taiyuan County and Shangdang County, Bingzhou will be acquired.

Of course, due to the limitations of the terrain, the best route to march from west to east into Bingzhou is almost the only one. So, how could people like Du Yu and Wang Jun not see this?

Since November 271, after confirming that Ji Han has started the national recruitment, Wang Jun set off from Taiyuan County and personally led 10,000 elite troops to station in Puban City, Hedong County, Sizhou. While constantly strengthening Puban City, he also recruited local residents, using Puban City as the midpoint, along the east bank of the Yellow River, south and north, and continuously built small forts. In short, if Shaanxi wants to enter Shanxi, there is only this part of the flattest area. I will guard this part - if you have the ability, go cross the Luliang Mountain!

After December, after the conscription of Jin State received results, Du Yu directly added 40,000 war soldiers and 10,000 civilians to Wang Jun.

Now, the state of Jin has distributed its troops on the Bingzhou front (including Hedong County in Sizhou) as follows:

The front-line commander Wang Jun was in Puban City, Hedong, with a force of 50,000.

The commander of the Front Army Du Yu was in charge of Shangdang County, with a force of 70,000.

Sima Fu, who had already died, was the sixth son of Taiyuan King Sima Gui and his son Sima Yong, who was in charge of Taiyuan County, with a force of 20,000.

In Du Yu's opinion, the key point of resisting Ji Han's Bingzhou strategy was not Bingzhou itself, but Puban City. Therefore, he arranged heavy troops in Hedong County, Sizhou. According to Du Yu's idea, Ji Han wanted to cross the Yellow River and grab the beach in this season, and then attack Puban City on the shallow river beach. It would be impossible for him to pay a price of more than 50,000 people.

Of course, Ji Han has had many military miracles over the years, so Puban City is not unavailable. Therefore, Du Yu did not suppress all his troops to Hedong County.

In Du Yu's plan, it would be fine if Ji Han took Puban City under heavy casualties or war miracles: Wang Jun's troops would retreat.

After Guan Yi took Puban, he was unlikely to attack Taiyuan when Shangdang had heavy troops stationed. Without Shangdang County, it would be meaningless to take Taiyuan County. Therefore, Du Yu's inference, if Guan Yi took Puban, he would definitely go to the east line to take Shangdang.

But is Shangdang so easy to take? Although the two most important checkpoints of Shangdang face south and east, they cannot restrict Guanyi from the west. However, it is fine if there is a large Loess Plateau between Hedong County and Shangdang County. The key is that Hedong County belongs to Sizhou, which is very close to Luoyang! In addition to being the world's largest city, Luoyang also has 80,000 national standing soldiers and 20,000 prince guards.

So, what should you do after you cross the Yellow River and take Puban? Go directly to capture Luoyang? Then my Shangdang troops will attack you behind you. Do you want to attack Shangdang? Okay, I will step back, lengthen your supply line, and fight you at Huguan-the Luoyang Central Army will attack your back.

This is Du Yu's Bingzhou strategy: first use Puban City to block the opponent's crossing the river and consume its vitality. Then put the Han army into two huge pliers composed of the Bingzhou Army and the Luoyang Central Army. It can be said that due to the natural terrain advantage, if Guan Yi's 150,000 troops really crossed the Yellow River and entered Puban, if they accidentally ended up being destroyed.

On June 20, 272, Guan Yi led 150,000 Han troops to Pubanjin.

In this season, the Yellow River has huge water volume and extremely fast flow. On the bank of the Yellow River, looking at the roaring Yellow River and the other side of the Yellow River, with flags waving and people shaking. The soldiers from Ji Han all looked pale and complained in their hearts.
Chapter completed!