99 years ago today, on March 12, 1926 (January 28, 1926), Japanese warships bombarded Dagu Exit. The "Emergency Declaration on the Opening of Diets for the Minister's Delegation" issued by the All-China Women's Federation of All walks of life Dagukou has a steep terrain and has always been a barrier to Beijing and Tianjin. In the First Opium War 150 years ago, British invaders marched on Dagu Pass in order to realize their plot to "threaten Tianjin and suppress Beijing." In the Second Opium War, the Dagu and Beitang areas became the main battlefields in the north, and the majestic Dagu Fort became a strong fortress against British and French imperialist aggression. From then to 1900, when the Eight-Power Allied Forces invaded China, the imperialist powers repeatedly invaded Dagukou, bringing severe disasters to the people of Tianjin. The people of Tianjin were not afraid of violence and waged a heroic and tragic struggle against the imperialist powers. On March 7, 1926, the National Army stationed at Dagu Pass in Tianjin discovered Feng-bound warships operating near Dagu Fort. The National Army immediately fired artillery to repel it, and on March 9 laid mines at Dagu Pass and blocked the port to prevent the invasion of the ship. On March 10, the embassies of 12 countries including Britain, France, Japan, the United States, and Italy met in China and believed that the National Army's blockade of Dagukou violated the Treaty of Xin Chou and demanded that the Beijing government remove all obstacles to entering Beijing. The National Army was forced to announce the opening of Dagu Port on March 12. However, in the afternoon of that day, the Japanese destroyer entered Dagu Pass but did not communicate with the National Army according to the signal and time agreed in advance, and another destroyer followed it. The National Army fired warning shots to stop, but the Japanese warships fired artillery at Dagu Exit. This led to the "Dagukou Incident". On March 14, the Northern District Committee of the Communist Party of China, the Beijing Prefectural Committee of the Communist Party of China and the Beijing Special Municipal Party Headquarters of the Kuomintang jointly held the "Beijing Nationals Anti-Japanese Aggression in Zhili Conference" to protest against Japanese warships 'shelling of Dagukou. On March 16, envoys from eight countries including Japan, Britain and the United States issued an ultimatum to the Beijing government, demanding that the Dagu Kou defense fortifications be demolished and that no obstacles should arise in the transportation from Beijing to the sea outlet. On March 17, the Kuomintang and the Communist Party held a joint meeting again. In response to the ultimatum, they unanimously adopted resolutions such as refuting the ultimatum on the same day, not allowing Japanese warships to bring ships into Hong Kong, and expelling the envoys of the eight countries from Beijing. At the same time, the meeting decided to ask the National Army to change its combat purpose and fight to abolish the unequal treaties. Later, representatives of the Kuomintang and the Communist Party met to petition the Ministry of Foreign Affairs and the State Council respectively, but they were suppressed by the Beijing government, resulting in the "March 18th" tragedy. The Northern District Committee of the Communist Party of China and the leftist Kuomintang led 100,000 people in Beijing to rally in front of Tiananmen Square to denounce imperialist aggression and the ruling government's traitorous behavior