The British victories over Burma in 1826 set the stage for a century in which the military history of Thailand was to be dominated by the threat of European colonialism. Initially, however, Siamese concern remained focused on its traditional rivals of Burma and Vietnam. Siam intervened in support of Britain against Burma in 1826, but her lackluster performance inspired Chao Anouvong's surprise attack on Korat. Lady Mo's resistance established her as a cultural heroine, and General Bodindecha's wars and defeat from the Vietnames two years later established him as a major figure in Thai military history. His campaign in the Siamese–Vietnamese War (1841–1845) was defeated militarily Siamese but took control over Cambodia. In 1849, weakening Burmese power encouraged revolt amongst the Burmese controlled Shan states of Kengtung and Chiang Hung. Chiang Hung repeatedly sought Siamese support, and ultimately Siam responded with the initial dispatch of forces in 1852. Both armies found difficulties campaigning in the northern mountainous highlands, and it took until 1855 before the Siamese finally reached Kengtung, though with great difficulty and the exhaustion of Siamese resources ultimately resulted in their retreat. These wars continued to be fought in the traditional mode, with war elephants deployed in the field carrying light artillery during the period, often being a decisive factor in battle. Meanwhile, the visible military weaknesses of China in the First and Second Opium Wars with Britain and later France between the 1830s and 1860s encouraged Siam to reject Chinese suzerainty in the 1850s. Siam, however, was under military and trade pressure itself from the European powers, and as King Rama III reportedly said on his deathbed in 1851: "We will have no more wars with Burma and Vietnam. We will have them only with the West."