Dagukou has always been a coastal defense fortress of the Ming and Qing dynasties in China, located at the mouth of the Haihe River. It is about 170 kilometers away from Beijing in the northwest, bordering the Bohai Sea in the east, the Haihe Plain in the west, and facing Tanggu across the river.

"When the land is Jiuhe Jin, the road leads to the seven provinces of boats and cars", Dagukou is known as the gateway of Beijing and Tianjin, the throat of sea and land. As early as the second year of Yongle in the Ming Dynasty, after Zhu Di built the capital of Beijing, he built a city and a guard in Tianjin, and built a pier and a cannon in Dagu Haikou; To the Qing Dynasty, the town camp of Dagu Association was placed; After the Ming army recovered Jiangnan, it built forts and gun emplacements in the north and south of Dagu, and the number of defense troops increased from 2,000 to 8,000.

However, when the Ming fleet attacked with a feint, the Qing court found that Tanggu's defensive forces and system were still incomplete. Because the place to be defended is not just a small piece, including the north bank of Dagu, the south bank, Caotougu, the stone crevice, the south beach, etc., these places are part of the defense system of Dagu fortress.

Moreover, for landing operations, if there are existing port facilities, it can certainly speed up the speed of carrying troops and supplies ashore. If not, it's not an insurmountable difficulty.

In other words, the Ming army could choose Tianjin and Tanggu as a breakthrough, or they could choose other locations to land. Of course, the biggest threat is Tianjin, but other areas cannot be ignored either. Moreover, after the successful large-scale landing of the Ming army, if only the garrison in Tianjin was relied on, it would seem that the troops were somewhat insufficient, or the depth of defense was insufficient.

After analyzing it in this way, if the Eight Banners of the Forbidden Brigade were dispatched to Shandong, it would be difficult to ensure the safety of the Beijing Division. And the movement of the Beijing division brought not only military influence, but also comprehensive passivity in politics. For the currently isolated form shì. As well as internal instability, the Manchus still saw it relatively clearly.

Therefore, the Manchus did not dare to ignore the safety of the Jingshi. And in Shandong, he made a fight with all the chips. In other words, the Qing court changed the place where troops were transferred, and transferred troops from the Xuanfu and Shanhaiguan areas to reinforce Shandong.

Although it is also an increase in troops, the Congjing Division is different from the Congxuanfu and Shanhaiguan. At least in terms of time, it was later, which undoubtedly bought the Ming army time to stabilize in Shandong.

And on the other hand. Although it was difficult for the Ming army to continue to increase its troops on a large scale due to the limitation of grain and grass materials, the work of raising materials did not stop for a moment. This can make the Ming army adopt refueling tactics and put a new force into Shandong with a scale of 2,000 men every ten days.

It would be a victory to be able to capture and occupy the base in the Bohai Bay, and it would be a good strategy to attract and deplete the Qing army in Shandong. With the current financial resources and manpower of the Manchu Qing Dynasty. As long as the Ming army engaged in a protracted war of attrition with it. It was enough to drag down the Manchus.

The Ming court had realized that the important point of the final victory of the war was not to give the Manchus time to adjust their respite. After the transportation of Cao Yun was cut off, it could only adopt the means of expropriation and extortion in order to support the war. The boiling of public resentment was the key factor for the Ming army to act as a liberator and be supported by support.

In fact, just as Zhu Yongxing and others expected, in the process of conquering Shandong, the Yu Qi Division, which was scattered all over Jiaodong, cooperated with the Ming army, making the development of the war extremely smooth. For example, Hao Jin of Qixia, Song Fan and Song Wan brothers of Laiyang, Song Jicheng father and son. There are also Jimo Huangpei and so on, or create chaos. Or the Kaesong response, a fierce and time-consuming siege battle that barely took place in the early days.

After the Ming army joined forces and cut off the connection between the Jiaodong Peninsula and the interior of Shandong, those isolated county towns had no intention of defending them, and those who surrendered and surrendered abounded.

Of course, this is also a manifestation of the fact that the people's hearts within the Manchu Qing Dynasty began to dissipate under the large shape of the entire reversal. This was not confined to Shandong, as the Manchus were even more shocked by the sudden rebellion in Huaiqing (in the Qinyang region of Cao Henan).

The Huaiqing area of Henan is close to Jifu, adjacent to Qin, Jin, Qi and Chu, and belongs to the land of "Sida", and the military commander stationed in Hebei is Cai Lu, the general soldier. Cai Lu and Yang Laijia, the chief military officer of Xiangyang, who had already surrendered anyway, were both the generals of the former Zheng Chenggong, who led his troops to surrender to the Qing Dynasty and gave them to the governor of Zuodu, and was promoted to serve as the chief military officer of Hebei. After the Ming army recovered the south of the river, Cai Lu received a letter of rebellion from Yang Laijia brought by the secret spy of the Ministry of National Security, and began to prepare for the attack. He secretly made shotguns, bought mules and horses, and under the guidance of secret spies of the Ministry of State Security, he ordered soldiers to go in armor in the name of fishing, which was actually a military exercise.

Although Cai Lu's uprising was planned to wait for the right time, due to a whistleblower, the Qing court received an urgent report of his important action, and immediately sent the Minister of the Interior, Amida, to lead the escort army to Huaiqing (Qinyang, Henan), where Cai Lu was stationed, to "inquire in detail about Cai Lu's reason for fishing", but in fact, it was necessary to arrest and ask the guilty.

This information was learned by the Ministry of State Security, and Cai Lu was immediately notified, so that he could prepare in advance and respond urgently. When Amida led the escort army to the eastern suburbs of Huaiqing, he was suddenly ambushed by Cai Lu's father and son and his nephew Cai Dingxi and others.

After Cai Lu and others defeated Amida, they immediately led the rebel officers and soldiers to break through the siege with the grain and grass of the treasury, and took advantage of the Qing court's encirclement and suppression of the army before they arrived, and entered the Taihang Mountain to defend it.

Militarily speaking, this was only a small defeat for the Manchus, but politically speaking, it was a crisis. Because Huaiqing was already part of the Kinkifu region, the rebellion of Cai Lu's father and son deeply shook the Qing ruling group, and a sense of crisis hit them from time to time, making it impossible for them to sleep peacefully.

"It's too late to extinguish, and Zhongzhou is in turmoil, and the soldiers and people are restless!" "The people are worried, and the chaos is hard to stop!" ”……

The rush came one after another, which made the Qing court feel that the safety of the Jingshi had been or would be threatened. Originally, Amida was sent to rush to Huaiqing, to surprise Cai Lu, and without waiting for him to deploy to resist, he was captured when he was caught off guard, and "pacified his first army", so that "the north and south of the river are as safe as before". However, it was not expected that the failure of the operation would cause more rebellions, and it was in the Kifu region, and the Qing court had to worry about it.

And the impact of Cai Lu's father's and son's rebellion is not only these, but the Qing court, which was originally not at ease with the green camp and the Han officials and generals, was even more vigilant at this time. However, the measures to be taken against will undoubtedly weaken the combat effectiveness of the Green Battalion and increase the centrifugal tendency of the Green Battalion generals.

Obviously, the Manchus were caught in a dilemma, both to take advantage of the green camp and to be on guard. Although this situation has existed for a long time, the effect is naturally different depending on the shape. When the Manchu Qing Dynasty won a series of victories, even if the green camp complained, they did not dare to resist; But after the Manchu Qing Dynasty was weak, the odds increased exponentially from thought to action. (To be continued......)