{{Warbox|
conflict=The British Expedition to Tibet
|campaign=
|colour_scheme=background:#bccccc
|date=December 1903 &ndash; September 1904
|place=Tibet 
|result=British victory, treaty enforced,<br>return to status quo.
|combatant1=22px United Kingdom
|combatant2=22px Tibet
|commander1=Brigadier J. R. Macdonald<br>Major Francis Younghusband 
|commander2=
|strength1=3,000 Combat soldiers<br>7,000 support troops
|strength2=Unknown, several thousands of peasant conscripts 
|casualties1= 202 KIA<br>411 Other deaths
|casualties2=Unknown, several thousands
|}}

The '''British expedition to Tibet''' in British Indian forces, seeking to prevent the twenty years before. Whilst British forces were remarkably successful in achieving their aims militarily, politically the invasion was very unpopular back in Britain, where it was virtually disowned post-war. The effects on Tibet, despite higher casualties and some economic disruption, were also not significant, and any changes were not long retained.

==Road to war==

The causes of the war are obscure, and it seems to have been primarily provoked by rumours circulating amongst the Viceroy, Lord Curzon, who decided to counter such a move by sending a diplomatic mission of 500 troops lead by a young officer named Major Francis Younghusband to Khamber Jong, a tiny Tibetan village north of Sikkim to meet Chinese and Tibetan representatives and discuss mutual non-aggression and trade agreements. The expedition arrived in June 1903 but by November no Chinese or Tibetan delegates had arrived and the force was recalled. Curzon decided at this stage to reinforce his message that foreign interference in the region would not be tolerated by dispatching a much larger armed force to the Tibetan capital Lhasa to dictate a treaty to the state's rulers.

Tibet's government, guided by the Dalai Lama was understandably unhappy about the presence of a large acquisitive foreign power dispatching a military mission to its capital, and began marshalling its armed forces. The government was fully aware that no help could be expected from the Chinese government, and so intended to use their arduous terrain and mountain-trained army to block the British path. The British authorities had also thought of the trials mountain fighting would pose, and so dispatched a force heavy with Balfour government was fully aware of the scale of the operation, or of the Tibetan intention to resist it.

==Initial advance==
thumb|left|Major [[Francis Younghusband leading a British force to Lhasa in 1904]]
The British army which departed Gnatong in Sikkim on the Guru, near Lake Bhan Tso. 

===The Battle of Guru===
Facing the vanguard of Macdonald's army and blocking the road was a 3,000 strong Tibetan force armed with primitive matchlock muskets and crouching behind rock sangers ready to fire on encroaching British forces. Their general rode to meet with Younghusband and Macdonald, but displayed his inexperience by not fortifying the western side of the pass, leaving his soldiers there exposed in plain view of his opponents. He hoped to prevent bloodshed, as the conflict was not yet a shooting war, and perhaps as a gesture of goodwill appears to have ordered his men to extinguish the fuses on their muskets, the relighting of which is a lengthy and difficult operation. Macdonald refused to accept the warnings of the Tibetan general and dispatched Sikh and Gurkha soldiers to disarm the Tibetan forces, who were unable to resist the advance due to their extinguished fuses, but still refused to give up their arms, resulting in a brawl amidst the sangers which while violent, was not yet deadly.

It was at this stage that war was irreparably declared, although the cause of it has never been established and probably never will be. British accounts insist that the Tibetan general became angry at the sight of the brawl developing and shot a Sikh soldier in the face rather than give up his modern pistol, prompting a violent response from the soldier's comrades which rapidly escalated the situation. The Tibetan accounts differ by claiming that the British tricked the general into extinguishing his troop's fuses and that once this was done the British opened fire first anyway, the fatal shot from the general's pistol only occurring once battle had been joined.

Whatever the truth of the opening round of the battle, the actual fighting did not last long. Once disarmed, the Tibetan forces attempted to retreat, but became entangled with each other and the steep landscape, opening them to disciplined rifle volleys from the Sikh and Gurkha regiments as well as the deadly fire of British Maxim Guns. Despite this withering attack, the Tibetan forces fell back in good order, refusing to turn their backs or run, and holding off cavalry pursuit at bayonet point. Half a mile from the battlefield the Tibetan forces reached shelter and were allowed to withdraw by Brigadier Macdonald. Behind them they left between 600 and 700 fatalities and 168 wounded, 148 of who survived in British field hospitals as prisoners. Amongst the dead was the general whose impetuous and inexperienced decision to extinguish his men's muskets had led to disaster. British losses were just a handful of wounded, including the unfortunate Sikh who had been shot in the face.

==The advance continues==
Past the first barrier and with increasing momentum, Macdonald's force crossed abandoned defences at Kangma a week later, and on the 9 April attempted to pass through Red Idol Gorge, which had been fortified to prevent passage. Macdonald ordered his Gurkha troops to scale the steep hillsides of the gorge and drive out the Tibetan forces ensconced high on their cliffs. This they began, but soon were lost in a furious blizzard, which cut all communications with the Gurkha force. Some hours later, exploratory probes down the pass encountered fire and a desultory exchange continued till the storm lifted around noon, which showed that the Gurkhas had by chance found their way to a position above the Tibetan troops. Thus faced with fire from both sides as Sikh soldiers pushed up the hill, the Tibetans moved back, again coming under severe fire from British artillery and retreated in good order, leaving behind 200 dead. British losses were again negligible.

It was clear that the mission was going to have to contest almost every pass and village it crossed, a problem Macdonald attempted to solve by splitting his forces, packets of several hundred being dispatched to various points on his route to drive in smaller Tibetan defences to speed the passage of the main force. Two minor actions occurred around this time, one on the 5 May at a fortified farm named Chang Lo involved an assault by an estimated 800 Tibetans on the British garrison of the fort, who were alerted by the cries of the Tibetan war whoops in time to form ranks and drive back the assailants with 160 dead. The other skirmish on the 9 May was possibly the highest action ever fought, when a Tibetan position at the Garo Pass (19,000 feet above sea level) was assaulted by Gurkha troops who climbed a vertical cliff under fire to outflank the Tibetans who were driven back by a charge of Gurkha, Sikh and British soldiers. For once, casualties were more evenly distributed, although the Tibetans still suffered heavily.

In the following two months, Macdonald collected his forces near Chang Lo and cleared minor obstacles with the intention of assaulting the main Tibetan stronghold at Gyantse Jong. Once this obstacle was cleared, the road to Lhasa would be opened, due to the removal of the small Tibetan forces occupying it by the dispersal of the British force. Gyantse Jong was however too tough for a small raiding force to take and it overlooked British supply routes, making it the primary target of Macdonald's army. On 28 June the final obstacle to the assault was cleared when a fortified monastery which covered the approach was taken in house to house fighting by Pathan soldiers.

Tibetan responses to the invasion so far had relied totally on static defences and sniping from the mountains at the passing column neither of which had proved effective, and apart from the failed assault on Chang Lo two months previously that had made no sallies against British positions or any aggressive movements against the besieging army. This attitude was a mix of justifiable fear of the Maxim Guns, and partly faith in the solid rock of their defences, but in every battle they were primarily let down by their poor weaponry and inexperienced leadership.

thumb|300px|[[Klosterfestung auf dem Berg Dzong in Gyangzê (1994)]]
Der '''Britische Tibetfeldzug''' (engl. ''British expedition to Tibet'') der Britischen Indienstreitkräfte von November 1903 bis September 1904 begann nach dem Scheitern von Verhandlungen zwischen Großbritannien um die Vorherrschaft in Zentralasien statt (Russischen Reiches auf  Russisch-Japanischen Krieg militärisch gebunden war. Die Bergfestung Gyangzê wurde gestürmt und Lhasa nach der Flucht des Dalai Lama eingenommen. General J. R. Macdonald und Major Francis Younghusband führten die Expedition an. 

Nach der Besetzung von Lhasa am 3. August 1904 begannen Verhandlungen der Briten mit dem  britische Empire war gescheitert. Zudem wies die Kaiserinwitwe Cixi (Tzu-Hsi) den Amban an, den ausgehandelten Vertrag nicht zu unterschreiben. 

Erst im April 1906 wurde der Vertrag von Lhasa von der chinesischen Regierung bestätigt und sie kam anstelle der Tibeter für die Kriegsentschädigung an das britisches Empire auf. Damit dokumentierte die chinesische Regierung ihren unveränderten Anspruch auf die Oberhoheit über Tibet (Suzeränität). 