and actively supported rebellions in Manipur, Assam and Arakan. Calcutta unilaterally declared Cachar and Jaintia British protectorates, and sent in troops. Cross border raids into Arakan, Manipur and from British territories vexed the Burmese. In January 1824, Bandula allowed Burmese troops into Cachar and Jaintia in pursuit of the rebels. The British sent in their own force to meet the Burmese in Cachar, resulting in the first clashes between the two. The war formally broke out on 5 March 1824, following border clashes in Arakan. At first, battle hardened Burmese forces were able to push back the British forces in Cachar, Jaintia and East Bengal. Instead of fighting in the difficult terrain, which represented "a formidable obstacle to the march of a European force", the British took the fight to the Burmese mainland. On 11 May 1824, a British naval force of 11,000 took Rangoon (Yangon), taking the Burmese by surprise. The Burmese forces tried multiple times to retake the city but failed. In April 1825, Bandula fell at the battle of Danubyu, and the British took up to Prome. The Burmese tried to retake Prome in a last-ditch attempt but were driven back in December. On 24 February 1826, the Burmese had to agree to British terms without discussion. Per the Treaty of Yandabo, Burma was forced to cede Arakan, Manipur, Assam and Tenasserim and pay a large indemnity of one million pounds sterling. The war was the longest and most expensive war in British Indian history. Fifteen thousand European and Indian soldiers died, together with an unknown number of Burmese army and civilian casualties. The campaign cost the British five million pounds sterling to 13 million pounds sterling (roughly 18.5 billion to 48 billion in 2006 US dollars) that led to a severe economic crisis in British India in 1833. For the Burmese, it was the beginning of the end of their independence. The Third Burmese Empire, for a brief moment the terror of British India, was crippled and no longer a threat to the eastern frontier of British India. The Burmese economy would struggle for years to repay the large indemnity. Second Anglo-Burmese War (1852) By 1851, tensions between Britain and Burma rose again. Using a fine of two British ships by the mayor of Rangoon as the casus belli, Lord Dalhousie, governor-general of India, sent an ultimatum to rescind the fine, remove the offending mayor, and