If the Northern Expedition to the Central Plains, how many troops the Wu army needs is not only Guo Chongtao's concern, but also Yang Wu and other generals.

To illustrate this issue, the first point is naturally to refer to several other Northern Expeditions in history.

To talk about the Northern Expedition, the Northern Expedition before the Wu State was mainly concentrated in the Eastern Jin Dynasty and the Northern and Southern Dynasties, especially the Northern Expedition of Zu Ti, Huan Wen and Liu Yu of the Eastern Jin Dynasty was the most famous.

Among them, the troops of Zu Ti's Northern Expedition were not many, and in the early days, they were just a few thousand northerners recruited privately; Later, after becoming famous, he received the support of the Eastern Jin Dynasty, which led to the Northern Expedition of tens of thousands of troops.

However, the achievements of Zu Ti's Northern Expedition were not much, and coupled with the constraints within the imperial court, Zu Ti's Northern Expedition soon ended in failure.

And the momentum of the Huanwen Northern Expedition was much greater than that of the ancestor of the Northern Expedition.

After all, Huan Wen had already controlled the Eastern Jin Dynasty to a certain extent, and there was a country's strength behind as a support, as well as the powerful army of the Beifu soldiers as a support, plus the north happened to be in chaos at that time, so the Northern Expedition of Huan Wen was greater than Zu Li's Northern Expedition in terms of strength, momentum and results.

However, the strength of the Huanwen Northern Expedition was actually not much, and the main army was only 40,000 or 50,000 people, plus the armies from all walks of life, the total strength was roughly about 100,000.

There were three Northern Expeditions to Huan Wen, of which the first two achieved some results, and the successful recovery of Luoyang brought great prestige to Huan Wen and paved the way for him to control the Eastern Jin Dynasty.

Unfortunately, Huan Wen's Third Northern Expedition ended in failure.

In contrast, the Northern Expedition of Emperor Liu Yu of the Song Dynasty can be said to be the closest to success.

Liu Yu's personal ability should be said to be the most outstanding one since Emperor Cao Cao of Wei, coupled with the elite Beifu elite soldiers, as well as the appropriate Northern Expedition strategy, Liu Yu's Northern Expedition once captured Shandong, Henan, and Guanzhong.

At that time, the area south of the Yellow River basically fell into the hands of Liu Yu, and the two important towns of Chang'an and Luoyang were also recovered by him.

It's a pity that after Liu Yu recovered Chang'an, his henchman Liu Muzhi, who stayed in Jiankang City to sit in the rear, suddenly fell ill and died, so that there was no credible person in the court, and Liu Yu was worried that there would be problems in the rear, so he led the main force to withdraw to Pengcheng.

More than a year later, the Jin generals who remained in Guanzhong had infighting, causing Chang'an to fall into the hands of the enemy again.

But even so, the east of Tongguan, south of the Yellow River, and the whole of Shandong were still under the control of Liu Song.

What really made Liu Song lose the opportunity of the Northern Expedition to unify the world was Liu Yu's death.

After Liu Yu's death, Emperor Wen of Song, who succeeded to the throne, hastily went on a northern expedition, which led to a big defeat. ”

Although Liu Yu's Northern Expedition failed, it still has extremely important reference significance for today's Wu State.

Although the specific number of troops dispatched by Liu Yu at that time is not recorded, it can be estimated through various means that the strength of the Jin army should be less than 200,000, and it is estimated that it is about 150,000.

Although these 150,000 troops have repeatedly won victories in the process of fighting with the northern regime, they have also exposed an important problem, that is, the lack of troops.

This lack of troops does not only mean that the troops directly used for the Northern Expedition are somewhat insufficient, but also that the troops left in the south are relatively insufficient.

At that time, although the Eastern Jin Dynasty had fallen under Liu Yu's control, the vast territory in the south was all won by Liu Yu with one hand and one foot.

In those areas where the mountains are high and the emperor is far away, if a large army is used to crusade, the local forces will inevitably "eat pot pulp to welcome the king's division"; But if the "Wang Shi" leaves, there will be a rebellion in the local area.

This state of rebellion and uncertainty has many similarities with the situation facing Wu today.

Don't look at the fact that all parts of the south are basically unified except for Lingnan, but if the main force of the Wu army goes to the Northern Expedition, who can guarantee that there will be no turmoil in the south?

And if the internal stability is not stable, I am afraid that it will be difficult for anyone who leads the Northern Expedition to go all out, and it is strange that the Northern Expedition can succeed in this case.

This time he sent troops to Jiangling, Yang Wu obviously still had 40,000 troops in Jinling, and Li Chengding's 20,000 troops in Fujian and Liangzhejiang, but even if the battle to attack Jiangling did not go well at the beginning, Yang Wu had no intention of using these troops, in order to be stable.

Even if the unified attack on Gangneung this time is not successful, then the troops can be withdrawn and go back to wait for the next time, there is always a chance to take Gangneung, and there is no need to rush for a while.

But if it is for the sake of a momentary speed, all the troops are used in Jiangling, maybe Yang Wu personally leads the army outside, which can indeed deter the internal Xiaoxiao and make them dare not move.

But in the case of the emptiness of the rear, what if someone really has the mentality of "seeking wealth and danger"?

At that time, although Yang Wu had the entire army of Wu in his hands, in the case of internal turmoil, how much morale and fighting spirit did these soldiers have?

How can the logistics of the more than 100,000-strong army be guaranteed?

What if you can't withdraw your troops quickly and safely in front of the enemy? What should I do if I am attacked by the enemy when I withdraw my troops?

After the withdrawal of the troops, how can an army that has been exhausted after a long battle can go thousands of miles away to quell the rebellion?

……

With so many problems, it can be said that as long as there is any internal chaos, the entire Wu Kingdom may fall into civil strife at that time, and this is the real fatal thing.

Therefore, even if the battle against Jiangling did not go smoothly at the beginning, Yang Wu had no intention of further increasing his troops, and would rather withdraw his troops or fight a decisive battle with the enemy than rashly increase his troops.

Moreover, the way of employing troops is not simply to pile up troops, but to integrate troops, strategy, logistics, and other aspects.

The Wu army used 80,000 troops this time alone for the forbidden army, plus 8,000 sailors, 3,000 cavalry, 3,000 Yulin troops, and other box troops, the total strength was more than 100,000.

As long as the troops are used properly, not to mention the next Jiangling, it is enough to defeat the entire Jingxiang; But if the troops are not used properly, even if more troops are added, what is the use? In vain, there will be hidden dangers in the rear.

Liu Yu's Northern Expedition, the number of troops dispatched was about 150,000, and the remaining troops remained in various parts of the south, which could ensure internal stability, but on the whole, the troops in Liu Yu's hands were still somewhat insufficient.

Except for the elite soldiers of Beifu, which can be relied on, the other armies are basically decorations.

If the Wu army is in the Northern Expedition, if it is the same as Liu Yu's Northern Expedition, using 150,000 troops, then the remaining army, including the Xiang army, should be more than 100,000, which can also ensure internal stability.

But the Northern Expedition of 150,000 troops, is this force enough?

Yang Wu was not sure, after all, there are still many differences between the current era and the era in which Liu Yu lived.

Both Liang and Jin will be the enemies of Wu, both of which have deep roots, and they have equally many troops, and the most important point is that these two countries are still mortal enemies, and the hatred and contradictions between each other are even greater than those between Wu and Liang.

In this way, perhaps the 150,000 Wu army could also achieve the same effect as Liu Yu's Northern Expedition, seizing the entire territory south of the Yellow River in one fell swoop.

However, if you want to defeat both the Liang State and the Jin State in one fell swoop, this is obviously impossible.

In addition to Liu Yu's Northern Expedition, which was known to all generals, Yang Wu, as a later generation, naturally also knew about another more influential Northern Expedition - Xu Da's Northern Expedition.

Although Zhu Yuanzhang has a lot of criticisms in the fundamental system of the Ming Dynasty he established because of his lack of knowledge, there is nothing to doubt about Zhu Yuanzhang's historical achievements.

To recreate China, these four words are enough to explain its historical achievements.

As for the rest, under this big question of right and wrong, it is only a matter of inconsequential details.

And Zhu Yuanzhang's restoration of China, the specific executor is Xu Da.

The strength of Xu Da's Northern Expedition was 250,000, perhaps in this era, 250,000 troops are very much, but in the era of the late Yuan Dynasty and early Ming Dynasty, 250,000 troops are really not much.

After hundreds of years of development in the Song Dynasty, the economy of the entire south has been greatly developed, and the population far exceeds that of the north.

In terms of the population of the whole of China, the population at the end of the Yuan Dynasty was much larger than it is today, and the forces of all parties were basically not the conscription system used as now, but the conscription system, which made the war between the various forces in the last years of the Yuan Dynasty The scale of the army used was much larger than now.

For example, Zhu Yuanzhang had as many as one million troops in his hands at that time, and the remnant Yuan's troops were also numerous.

However, many of the troops actually used were only 250,000.

The rest of the army is naturally left in the rear, and Zhu Yuanzhang personally sits in charge, which is enough to ensure the stability of the rear.

In this way, there was a stable rear to provide continuous support to the Northern Expeditionary Army, coupled with Xu Da's outstanding ability to command troops, so he was able to capture Dadu in just over a year, and basically completed the important task of unifying the world.

From this point of view, Yang Wu felt that if Wu wanted to go on a northern expedition in the future, it should be enough to use 200,000 forbidden troops, and if some of Liang's troops were incorporated on the way to the Northern Expedition, then there would be basically no problem in the Northern Expedition to eliminate Liang.

And in the rear, it is also necessary to leave enough troops to ensure the stability of the rear.

In this way, Yang Wu felt that the Wu army needed at least 300,000 forbidden troops, plus the box troops left behind in various places, the total strength was about 400,000.

With so many troops, and with the right strategy, the Northern Expedition could be a success!

In fact, in the early years of the Song Dynasty, the strength of the forbidden army in the era of Zhao Kuangyin was 200,000, and it only increased to more than 300,000 in the era of Zhao Kuangyi.

Considering that the enemies faced by Wu today are much stronger than those of the Southern Tang Dynasty and other regimes faced by the Song Dynasty when it unified the world, Yang Wu felt that 300,000 forbidden troops were the most suitable troops, and it was also the limit of Wu's finances.