The president and vice-president of the Commune were somewhat careless and neglected to guard against the defense of the city of Paris.

In the early morning of that day, the Provisional Government forces, under the orders of the President of the Provisional Government, Adolfo Thiers, began to bombard Paris and launched an attack on the Pont de la Neuilly, west of Paris.

After hours of fierce fighting between nearly 10,000 soldiers of the Paris Commune and more than 20,000 Provisional Government troops, they abandoned positions such as the Pont de Nail. The soldiers of the Paris Commune retreated into the city of Paris in defeat. But the sound of Versailles' artillery woke up Paris, and the Paris Commune immediately decided to attack Versailles by making a detour from the other direction.

As a result, the Commune hastily mobilized nearly 30,000 soldiers and marched to Versailles on the south and east routes. Nearly 20,000 men attacked from the east and repelled the gendarmerie of the Provisional Government Army, but were blocked and retreated by a strong enemy force of nearly 50,000 men; The 10,000 troops of the Paris Commune marched from the southeast, won the first battle, and were forced to retreat 5 kilometers from Versailles due to lack of ammunition and reinforcements, but unfortunately fell into the enemy's heavy encirclement, and the president of the Paris Commune, Louis Eugène Valland, was captured and heroically killed; The remaining nearly 6,000 men were defeated, and after the capture of Ruey, they heard the news of the withdrawal of friendly troops to Paris on the eastern route, and the enemy had arrived in large numbers, and was forced to retreat in desperation.

However, the most unfortunate thing is that the remaining 6,000 retreating Paris Commune troops were stopped by the Provisional Government Army in a fierce battle when they were about to retreat to the city of Paris, suffered a heavy defeat, and finally annihilated the entire army. The 10,000 people on the south road were the main force of the Paris Commune, of which the backbone of the Paris Commune members were mainly concentrated in this team, and the fiasco of this armed force led to heavy losses among the members of the Paris Commune, among which even the president of the Commune and 12 permanent members died heroically, completely making the leading institutions of the Paris Commune on the verge of destruction.

The Paris Commune's initiative in this attack was due to the command error of the person in charge of the Commune and the lack of preparation and effective command for large-scale military operations, resulting in the failure of the attacking troops to carry out their own affairs. This made Paris, which was already weak, even worse. And for the Provisional Government Army, there is a great opportunity.

Adolf Thiers directly ordered 120,000 government troops to begin to encircle Paris from the east and south. At this time, the only remaining 15,000 soldiers of the Commune in Paris were the 15,000 soldiers who had fled, and more than 20,000 reservists had been recruited. But the more than 20,000 reserve troops, although many of them could fire muskets, were not effectively organized, and not many of them could fire artillery, so the military strength of the Paris Commune was even weaker.

The Provisional Government Army, with its significant superiority, soon forced its way across the Seine and captured the Issy and Wangfu forts. Soon, 110,000 government troops began to gather heavy artillery and bombard Paris, and the whole of Paris was in danger. At this time, a part of the Marseille legion, a total of 30,000 soldiers, also arrived in the southeast of Paris, preparing to join the main force of the Marseille legion dozens of kilometers away to encircle the German army north of Paris.

At the same time, a peaceful merchant group that had just heard of the Paris uprising and had arrived from Dublin, Ireland, arrived in the northern suburbs of Paris, and the leader of this merchant group was Friedrich Uhgus.

Friedrich Uhgus's caravan could no longer enter the city, and they circled around Paris halfway around the city, just in time to encounter the 30,000-strong army of the Marseille legion. Coincidentally, in this Marseille army, one of the generals who led an infantry division and 2 artillery battalions, Hmgus happened to deal with him, and, crucially, this Marseille general named Cluz was also a supporter of Mecas and Uhges, he was originally a worker, and had always yearned for the Paris Revolution and the political ideas of the Jacobins. After two days of coordination and confirmation, Friedrich Uhgues and General Kruse, led 7,000 Marseille progressive soldiers into Paris, joined the Paris Commune and became the military force guarding the Paris Commune.

The President of the Provisional Government, Adolfo Thiers, and the commander of the Marseille regiment were furious and immediately ordered the government troops to attack Paris. With the addition of the Marseille Legion, as many as 160,000 soldiers and more than 500 artillery pieces, they bombarded the city of Paris. At this critical juncture, in order to stimulate the fighting spirit of the members and the Parisian people, the vice president of the Paris Commune, Bautier, composed the poem "Internachonelle", and sang it loudly using the tune of "La Marseillaise", which aroused the fighting enthusiasm of the people of the whole Paris.

More than 50,000 Parisians joined the Commune's army, including nearly 5,000 retired soldiers. With the 7,000 Marseille soldiers led by General Cleuse, and the 35,000 Commune troops of the Paris Commune, including reservists, the Commune's military strength in Paris now reached 92,000.

Because of the sacrifice of the former president of the commune, Walland, and the sacrifice of many more permanent members of the commune, the vice president Bautier decided to make up the number of permanent members of the commune. Bautier strongly recommended Friedrich Mügs and Cleuz as permanent members.

Under his strong recommendation, coupled with the huge fame of Uhgus, Uhgus was directly elected as the new president of the Paris Commune, Bautier became the president, and General Cluz became a permanent member of the society, in charge of military operations.

Friedrich Uhgus was a military theorist, and after learning of the situation outside the city and inside Paris, he immediately realized the serious military shortcomings of the original Commune, so he immediately ordered Cleuse to be the commander-in-chief of the Paris Commune army as the new president, and all the Commune troops in Paris were handed over to General Crüz to be under the unified command of General Clausez to defend the city of Paris.

Moreover, he was ecstatic to find that there were 200,000 rifles, 1,200 cannons hidden in three arsenals in the city of Paris, five artillery batteries and a well-fortified ring fortress area scattered on several high ground in the city of Paris, as well as enough ammunition, food and billions of francs in the Bank of France to be used for several years.

What's more, Well, Gus understands that the best defense is offense. In the city of Paris, as long as there are enough artillery to use 800 or 1,000 of the 1,200 cannons, the city of Paris will be impregnable. As long as it is a little more stable, more troops can be recruited in the city of Paris, and after sending troops to train, they can massacre Paris and establish a French Republic that truly belongs to the Paris Commune.

It has to be said that with the theoretical guidance and directional control of this great theoretician and president of the Paris Commune, coupled with the support of the people of Paris mobilized by the workers' leader and vice president of the Paris Commune, Bautier, and the participation of the real military commander, General Cruz, the Paris Commune quickly rejuvenated and defended Paris as impregnable.

Moreover, because the 1,200 cannons in the city of Paris, this number, was much more than the Provisional Government Army outside the city, General Cruz pressed all the artillery he brought to the city, and also trained thousands of artillerymen, although the artillery shooting was not very accurate, but it could not stand the position advantage on the head of the city and the sufficient shells and gunpowder in the arsenal, the government troops outside the city could not withstand it at all, and after more than a month, the Provisional Government army was quickly defeated, and the Marseille legion was persuaded by the messenger sent by General Cluse, He also fought back, completely crushing the Provisional Government's troops, and the Provisional Government's president, Adolf Thiers, fled directly into the Prussian army to the north.

The Marseille legion directly declared allegiance to the regime of the Paris Commune. At this point, the Paris Commune finally took full control of the political position of the city.