On September 6, 1879, more than 20 ships of the British expeditionary fleet sailed to the northern coastal areas controlled by the royalists, Córdoba, Recife, Maceio and other coastal towns were deterred by British ships, on September 8, 30,000 Brazilian Republican troops landed in the southern port of Bahia, Port Seguru, on September 9, more than 3,500 royalist defenders were attacked by the Republican Army, evacuated Port Saiguru and retreated to the northern inland area, on September 12, the Republican Army went all the way north, Recovering Ireus and Itacare, which had been controlled by the royalist forces, on 14 September, the republican forces occupied the island of Tignare and confronted the royalist forces stationed in Valença across the sea.

On 17 September, Auston, the British minister to Brazil, mediated a dispute between the Republican and Royalist factions, and the two sides agreed to use the line of Tignare, Valenza, and Serra Grande as the ceasefire line, and that eight and a half states, north of the ceasefire line, including the northern part of Bahia, Maranhão, Piauí, Ceará, Rio Gro Norte, and Pernambuco, would be under the control of the royalist forces, and that the states of Amapá, Pará, and Tocantins south of the ceasefire line and in the northern part of Brazil would be under the control of the republican government. The armies of both sides are to retreat to the areas under their control and are not allowed to cross the line and provoke.

On September 5, the day before the British expeditionary fleet supported the Brazilian Republican Army to launch a coastal offensive, the armistice negotiations between Han and Britain, Brazil, and Chile were launched again, and with the foreshadowing of the first negotiation, the second negotiation went straight to the point at the beginning, and the representatives of the two sides eliminated some of the conditions that were only to raise the asking price and could not be accepted by the other side, and each put forward relatively sincere terms for peace talks, and then the representatives of Britain, Brazil, and Chile respectively unilaterally negotiated with Han on the conditions proposed by their own countries, on September 14, At the end of the first round of negotiations, Han reached a preliminary consensus with Britain and Brazil on the Argentine question, and the republican governments of Britain and Brazil recognized the annexation and occupation of Argentina and Uruguay by Han, while the Chilean government opposed Han to bring the land on the Pacific side of the Patagonian wasteland under its rule.

On September 15, Paraguay's king López Jr. was blocked from entering the state of São Paulo, and under pressure from the British, he also joined the armistice negotiations.

On September 16, the Han State made concessions on the issue of overseas colonial strongholds, and was willing to hand over the Kismayo and Mtwara strongholds to the British government, and at the same time the Han government promised to demilitarize the Natuna Islands, and the Han side stopped building new fortifications on the Natuna Islands, withdrew the redundant troops, and limited the number of troops stationed on the islands to 400 people, and because Songkhla was nominally part of the territory of the Kingdom of Thailand, the Han government refused to agree to hand over Songkhla to the British Malay colonial government. The Malay Peninsula is the choke point of the Malacca shipping lanes in Asia, and in South American affairs, the British did not care that the Han people occupied a few more pieces of land, but in the face of foreign forces that might threaten the Strait of Malacca, the British were not willing to make concessions at all, in order to reach peace talks as soon as possible, Hu Yaji asked Li Mingyuan for instructions, and expressed his willingness to make concessions, and the Han government promised to withdraw all the troops stationed in Songkhla before 1880 and not interfere again

Songkhla's internal affairs, and in exchange, the British government should respect Songkhla's sovereignty and refrain from annexing Songkhla's territory without cause.

An armistice agreement was reached with the British, who had the right to decide, and Chile was left, even if it was seriously dissatisfied, and finally had to make concessions under the guarantee that Huyaki would not interfere in the course of the Pacific War, and acquiesced in the Han State's ownership of the Pacific side of the Patagonian wasteland, and the Han government and Chile took Valdivia as the dividing line, and as a result, the Han government obtained access to the sea including the Pacific region, and the two port cities, including Valdivia and Puerto Montt, will become the next twenty years. Two new migrant transport ports.

The signing of the "Rio de Janeiro Treaty", the Han State officially obtained Argentina, Uruguay, and the access to the sea on the Pacific side of the Patagonian wasteland, and more than 80% of the La Plata Plain area fell under the control of the Han State, and the Han State obtained the foundation of becoming a rising power, and the British resolved the crisis of the Brazilian Republican Government through negotiations, and got rid of the embarrassing situation of being mired in the quagmire of the South American War. Without the support of the strong military force of the Han State, the Kingdom of Paraguay, which was reckless and the domestic economy was deteriorating, could not unite Peru and Bolivia, and in the face of the situation that the governments of Paraguay, Peru and Bolivia were fighting separately, the politicians of Buckingham Palace were convinced that the prestige of the British Empire and the deterrence of the expeditionary fleet alone were enough to restore the control of British capital over Peru and Bolivia. will be overthrown and ousted because of the intensification of internal contradictions.

The four-nation alliance of Han, Paraguay, Bolivia and Peru came to an end because of the signing of the "Rio de Janeiro Agreement", and in fact, during the second Argentine war, the four-nation alliance existed in name only.

Ten years have passed, the balance of power between the four countries has undergone subversive changes, Peru and Bolivia are full of warlords, relying on coups to come to power of the presidents of the country, in the past ten years, there have been several waves of people, the military strength and economic strength of the two countries are still stagnant, Paraguay, even if the territorial area has expanded to 1.2 million square kilometers, López Jr. has successively incorporated Brazil's southern Magrosso, northern Goiás, and parts of Mato Grosso into his rule, but in terms of population, Paraguay's population has only increased to 600,000, a huge disparity compared to the 8 million in Paraguay.

The population, economy, and military strength all surpassed the other three countries, and the continuation of the Quadruple Alliance not only cost financial resources and incur the scruples of the other three countries, but also caused the British to be jealous for no reason.

The Quadruple Alliance has lost its role ten years ago, and the annexation and integration of Argentina, Uruguay, and other newly occupied areas of the Han State no longer needs to win over Peru and Bolivia to warm up, so it is a relatively cost-effective deal for the Han side to conform to the wishes of the British and sacrifice the interests of Peru, Bolivia, and Paraguay in exchange for a precious period of peaceful development.

The fire on the first line of the Atlantic in South America stopped, and the Pacific coast of the other line, without the containment of the Han ** team, the Chilean Navy held back its anger and went north along the coastline to find trouble with Bolivia and Peru, on September 20, Iquique fell, on September 22, the Chilean Navy besieged Lima, the capital of Peru, and the Peruvian army in the city failed to break the siege of the Chilean army twice out of the city, on September 26, two large ironclad ships of the Chilean Navy took advantage of the high tide period of the sea to sail into the port and bombard Lima City, on September 28, 20,000 Chilean Army, with the cooperation of naval ships and guns, attacked Lima City, and the Peruvian president was unfortunately captured and forced to sign a humiliating armistice treaty, ceding the provinces of Moquegua, Tacna, Tarapaca, Arica, and Iquique to Chile.

On October 2, the Bolivian government was unable to support itself and had to admit the fact that Chile occupied Antofagasta, so far, the guano war that lasted for four years in history ended ahead of schedule, and Chile lost the ownership of the southern Patagonia wilderness area, and seized important saltpeter sources from Peru and Bolivia, and compared with history, Chile obtained two additional provinces of Moquegua and Tacna from Peru, which is not too much of a loss in comparison.