South America 1900: Thousand Days' War

Long unstable, Colombia collapsed into civil war in 1899, when the Liberal Party revolted against the ruling Conservative Party’s rigging of elections and suppression of opposition. Although the Conservatives won this Thousand Days’ War in 1902, resentment remained in much of the country and in Panama in particular.

Main Events

3 Oct 1899 Essequibo Arbitration

Under the leadership of the United States, the British Guiana-Venezuela boundary dispute was successfully settled by a Tribunal of Arbitration in Paris on 3 October 1899. According to the award, most of the Essequibo River Basin - 90% of the disputed territory - was to remain in British hands, while the headwaters of the Cuyuni would belong to Venezuela. Although disappointed, Venezuela accepted the ruling.in wikipedia

18 Oct 1899-21 Nov 1902 Thousand Days’ War

Civil war broke out in Colombia when the opposition Liberal Party accused the ruling Conservatives of maintaining power through fraudulent elections and started a rebellion in Santander. Over the course of three years fighting, the Conservatives successfully confined the main Liberal armies to Panama and the Atlantic coast, leading the latter to surrender in exchange for amnesty in October. By this time, the United States had sent in its navy to protect its interests, and the definitive peace treaty was signed aboard the USS Wisconsin on 21 November 1902.in wikipedia

15 Mar-25 Apr 1900 Suppression of Acre

A Brazilian flotilla arrived in Acre via the Amazon, dissolving the Independent State of Acre in Puerto Alonso (Porto Acre) and arresting its president, Luis Gálvez Rodríguez Arias. In abidance with the 1867 Treaty of Ayacucho, Brazil restored the territory to Bolivia on 25 April.in wikipedia