Han–Sierran War

{{Infobox Military Conflict1 | title = Supported by | TBD | title = Supported by | Meiji Japan }} }}The Han–Sierran War (Han: 战争的内华达人 ; 전쟁뇨시엘라진, {{W|Transliteration|tr.}} Jounjéng nyo Sierrajin) was an armed conflict between Sierra and the Yi dynasty, lasting from 17{{sup|th}} March 1900 until 26{{sup|th}} March 1904.
 * conflict     = Han–Sierran War
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 * date        = 17{{sup|th}} March 1900 – 2{{sup|nd}} June 1905
 * place       = Han archipelago
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 * Sierranƒƒ victory
 * Treaty of Hanyang signed
 * The Yi dynasty becomes an Sierran {{W|protectorate}}, under Sierran {{W|suzerainty}} while retaining nominal {{W|sovereignty}}
 * Yi Household is ousted from power
 * combatant1  = Flag of Sierra.svg Sierra {{Collapsible list
 * combatant2  = Haniflag.png Yi dynasty {{Collapsible list
 * strength2   = 200,000
 * strength1   = 50,000
 * casualties2 = 120,000
 * casualties1 = 5,000

Conflict first erupted between the two sides when the conservative faction of the Han state-council, led by General Mé Ling and Empress Ming, decided to assault a group of Sierran troops stationed in Hanyang. Seeking to reestablish the abandoned {{W|isolationism|isolationist}} foreign policy and returning the Yi dynasty to its pre-opening enclosure, the conservative faction objected to the peace terms proposed by the Sierrans. Furthermore, the conservative faction pressured the central government to nullify previous {{W|unequal treaty|unequal treaties}} signed between it and Sierra, denying the Sierrans access to Hani and robbing them of their {{W|extraterritoriality|extraterritorial}} rights.

Refusal by the Hans to accept its peace terms and to reinstate friendly relations prompted the Sierra to use this as a {{W|casus belli}} to justify the {{W|annexation}} of the strategically important {{W|Philippines|Han archipelago}}. Despite some rigorous {{W|modernisation}} prior, its core regions quickly succumbed to Sierran occupation, specifically the {{W|Central Luzon|Central Rusan plain}}, the areas surrounding the {{W|Manila Bay|Hanyang Bay}}, and the {{W|Cagayan Valley|Gaya Valley}}. However, in mountainous regions, resistance was thick, lengthening the war by an additional three years.

The war effectively ended on March 26, 1904, and ended with the {{W|annexation|incorporation}} of the Yi dynasty as a {{W|protectorate}} as per the Treaty of Hanyang. The treaty forced it to give its {{W|suzerainty}} to the Sierra, while maintaining nominal {{W|sovereignty}}, and ending its traditional {{W|tributary state|tributary}} relationship with the Chinese. Guerilla fighting among some remote regions continued, but posed little threat to the Sierran hegemony over the archipelago.