There is an ongoing territorial dispute between China and India over the sovereignty of two relatively large, and several smaller, separated pieces of territory at their border. The territorial disputes between the two countries stem from the legacy of British colonial-era border agreements, particularly the McMahon Line in the eastern sector, which was drawn in 1914 during the Simla Convention between British-ruled India and Tibet but was rejected by China. In the western sector, the dispute involves Aksai Chin, a region historically linked to the princely state of Jammu and Kashmir but effectively controlled by China after the 1962 war. The lack of mutually recognized boundary agreements has led to ongoing tensions and occasional military clashes.
The first of the territories, Aksai Chin, is administered by China and claimed by India; it is mostly uninhabited high-altitude wasteland but with some significant pasture lands at the margins. It lies at the intersection of Kashmir, Tibet and Xinjiang, and is crossed by China's Xinjiang-Tibet Highway. The second of the disputed territories, Arunachal Pradesh, is a region south of the McMahon Line. The area was formerly known as the North-East Frontier Agency, and is now administered by India as a state. The McMahon Line was signed between British India and Tibet to form part of the 1914 Simla Convention, but the latter was never ratified by China. China rejected the McMahon Line agreement, stating that Tibet was not independent when it signed the Simla Convention, and maintains a claim over the area.
The 1962 Sino-Indian War was fought in both disputed areas. Chinese troops attacked Indian border posts in Ladakh in the west and crossed the McMahon Line in the east. There was a brief border clash in 1967 in the region of Sikkim, despite there being an agreed border in that region. In 1987 and in 2013, potential conflicts over the Lines of Actual Control were successfully de-escalated. A conflict involving a Bhutanese-controlled area on the border between Bhutan and China was successfully de-escalated in 2017 following injuries to both Indian and Chinese troops. Multiple skirmishes broke out in 2020, escalating to dozens of deaths in June 2020.
Agreements signed pending the ultimate resolution of the boundary question were concluded in 1993 and 1996. This included "confidence-building measures" and the Line of Actual Control. To address the boundary question, formalised groups were created, such as the Joint Working Group (JWG) on the boundary question. It was to be assisted by the Diplomatic and Military Expert Group. In 2003, the Special Representatives (SRs) mechanism was constituted. In 2012 another dispute resolution mechanism, the Working Mechanism for Consultation and Coordination (WMCC), was framed.
Background
The territorial disputes between the two countries result from the historical consequences of colonialism in Asia and the lack of clear historical boundary demarcations. There was one historical attempt to set a proposed boundary, the McMahon Line, by the United Kingdom during the 1913–1914 Simla Convention. The Republic of China rejected the proposed boundary. The unresolved dispute over the boundary became contentious after India gained its independence and the People's Republic of China was established. The disputed borders are complicated by the lack of administrative presence in the disputed areas, which are remote. Disagreements also result from the fact that the Line of Actual Control has never been distinctly demarcated, with China and India often disagreeing over its precise location.
Aksai Chin
From the area's lowest point on the Karakash River at about 14,000 feet (4,300 m) to the glaciated peaks up to 22,500 feet (6,900 m) above sea level, Aksai Chin is a desolate, largely uninhabited area. It covers an area of about 37,244 square kilometres (14,380 sq mi). The desolation of this area meant that it had no significant human importance other than ancient trade routes crossing it, providing brief passage during summer for caravans of yaks from Xinjiang and Tibet.
One of the earliest treaties regarding the boundaries in the western sector was issued in 1842 following the Dogra–Tibetan War. The Sikh Empire of the Punjab region had annexed Ladakh into the state of Jammu in 1834. In 1841, they invaded Tibet with an army. Tibetan forces defeated the Sikh army and, in turn, entered Ladakh and besieged Leh. After being checked by the Sikh forces, the Tibetans and the Sikhs signed the Treaty of Chushul in September 1842, which stipulated no transgressions or interference in the other country's frontiers. The British defeat of the Sikhs in 1846 resulted in transfer of sovereignty over Ladakh to the British, and British commissioners attempted to meet with Chinese officials to discuss the border they now shared. However, both sides were sufficiently satisfied that a traditional border was recognised and defined by natural elements, and the border was not demarcated. The boundaries at the two extremities, Pangong Lake and Karakoram Pass, were reasonably well-defined, but the Aksai Chin area in between lay largely undefined.
The Johnson Line
W. H. Johnson, a civil servant with the Survey of India, proposed the "Johnson Line" in 1865, which the British claimed Aksai Chin to be in Jammu and Kashmir. This was the time of the Uyghur occupation, when China did not control Xinjiang, so this line was never presented to the Chinese. Johnson presented this line to the Maharaja of Jammu and Kashmir, who then claimed the 18,000 square kilometres contained within his territory and by some accounts he claimed territory further north as far as the Sanju Pass in the Kun Lun Mountains. The Maharajah of Jammu and Kashmir constructed a fort at Shahidulla (modern-day Xaidulla), and had troops stationed there for some years to protect caravans. Eventually, most sources placed Shahidulla and the upper Karakash River firmly within the territory of Xinjiang (see accompanying map). According to Francis Younghusband, who explored the region in the late 1880s, there was only an abandoned fort and not one inhabited house at Shahidulla when he was there – it was just a convenient staging post and a convenient headquarters for the nomadic Kirghiz. The abandoned fort had apparently been built a few years earlier by the Dogras. In 1878, the Chinese had reconquered Xinjiang, and by 1890, they already had Shahidulla before the issue was decided. By 1892, China had erected boundary markers at Karakoram Pass.
In 1897, a British Raj military officer, Sir John Ardagh, proposed a boundary line along the crest of the Kun Lun Mountains north of the Yarkand River. At the time, Britain was concerned at the danger of Russian expansion as China weakened, and Ardagh argued that his line was more defensible. The Ardagh line was effectively a modification of the Johnson line and became known as the "Johnson-Ardagh Line".
The Macartney-Macdonald Line
In 1893, Hung Ta-chen, a senior Chinese official at St. Petersburg, gave maps of the region to George Macartney, the British consul general at Kashgar, which coincided in broad details. In 1899, Britain proposed a revised boundary, initially suggested by Macartney and developed by the Governor General of India Lord Elgin. This boundary placed the Lingzi Tang plains, which are south of the Laktsang range, in India, and Aksai Chin proper, which is north of the Laktsang range, in China. This border, along the Karakoram Mountainss, was proposed and supported by British officials for several reasons. The Karakoram Mountains formed a natural boundary, which would set the British borders up to the Indus River watershed while leaving the Tarim River watershed in Chinese control, and Chinese control of this tract would present a further obstacle to Russian advance in Central Asia. The British presented this line, known as the Macartney-MacDonald Line, to the Chinese in 1899 in a note by Sir Claude MacDonald. The Qing government did not respond to the note. According to some commentators, China believed that this had been the accepted boundary.
1899 to 1947
Both the Johnson-Ardagh and the Macartney-MacDonald lines were used on British maps of India. Until at least 1908, the British took the Macdonald line to be the boundary, but in 1911, after the collapse of central power in China, and by the end of World War I, the British officially used the Johnson Line. However, they took no steps to establish outposts or assert actual control on the ground. In 1927, the line was adjusted again as the government of British India abandoned the Johnson line in favour of a line along the Karakoram range further south. However, the maps were not updated and still showed the Johnson Line.
From 1917 to 1933, the Postal Atlas of China, published by the Government of China in Peking, had shown the boundary in Aksai Chin as per the Johnson line, which runs along the Kunlun Mountains. The Peking University Atlas, published in 1925, also put the Aksai Chin in India. When British officials learned of Soviet officials surveying the Aksai Chin for Sheng Shicai, warlord of Xinjiang in 1940–1941, they again advocated the Johnson Line. At this point, the British had still made no attempts to establish outposts or control over the Aksai Chin, nor was the issue ever discussed with the governments of China or Tibet, and the boundary remained undemarcated at India's independence.
Since 1947
Upon independence in 1947, the government of India fixed its official boundary in the west, which included the Aksai Chin, in a manner that resembled the Ardagh–Johnson Line. India's basis for defining the border was "chiefly by long usage and custom". Unlike the Johnson line, India did not claim the northern areas near Shahidulla and Khotan. From the Karakoram Pass (which is not under dispute), the Indian claim line extends northeast of the Karakoram Mountains north of the salt flats of the Aksai Chin, to set a boundary at the Kunlun Mountains, and incorporates part of the Karakash River and Yarkand River watersheds. From there, it runs east along the Kunlun Mountains, before turning southwest through the Aksai Chin salt flats, through the Karakoram Mountains, and then to Pangong Lake.
On 1 July 1954, Prime Minister Nehru wrote a memo directing that the maps of India be revised to show definite boundaries on all frontiers. Up to this point, the boundary in the Aksai Chin sector, based on the Johnson Line, had been described as "undemarcated".
Trans-Karakoram Tract
The Johnson Line is not used west of the Karakoram Pass, where China adjoins Pakistan-administered Gilgit–Baltistan. On 13 October 1962, China and Pakistan began negotiations over the boundary west of the Karakoram Pass. In 1963, the two countries settled their boundaries largely based on the Macartney–MacDonald Line, which left the Trans Karakoram Tract approximately 5,180 km2 (2,000 sq mi) to 5,300 km2 (2,000 sq mi) in China, although the agreement provided for renegotiation in the event of a settlement of the Kashmir conflict. India does not recognise that Pakistan and China have a common border, and claims the tract as part of the domains of the pre-1947 state of Kashmir and Jammu. However, India's claim line in that area does not extend as far north of the Karakoram Mountains as the Johnson Line. China and India still have disputes over these borders.
The McMahon Line
British India annexed Assam in northeastern India in 1826 by the Treaty of Yandabo at the conclusion of the First Anglo-Burmese War (1824–1826). After the subsequent Anglo-Burmese Wars, the whole of Burma was annexed, giving the British a border with China's Yunnan province. In 1913–14, representatives of the United Kingdom, China, and Tibet attended a conference in Simla, India, and drew up an agreement concerning Tibet's status and borders. The McMahon Line, a proposed boundary between Tibet and India for the eastern sector, was drawn by British negotiator Henry McMahon on a map attached to the agreement. All three representatives initialled the agreement, but Beijing soon objected to the proposed Sino-Tibet boundary and repudiated the agreement, refusing to sign the final, more detailed map. After approving a note which stated that China could not enjoy rights under the agreement unless it ratified it, the British and Tibetan negotiators signed the Simla Convention and a more detailed map as a bilateral accord. Neville Maxwell states that McMahon had been instructed not to sign bilaterally with Tibetans if China refused, but he did so without the Chinese representative present and then kept the declaration secret.
V. K. Singh argues that the basis of these boundaries, accepted by the British Raj and Tibet, was that the historical boundaries of India were the Himalayas and the areas south of the Himalayas were traditionally Indian and associated with India. The high watershed of the Himalayas was proposed as the border between India and its northern neighbours. India's government held the view that the Himalayas were the ancient boundaries of the Indian subcontinent and thus should be the modern boundaries of British India and later the Republic of India. Chinese boundary markers, including one set up by the newly created Chinese Republic, stood near Walong until January 1914, when T. O'Callaghan, an assistant administrator of North East Frontier Agency (NEFA)'s eastern sector, relocated them north to locations closer to the McMahon Line (albeit still South of the Line). He then went to Rima, met with Tibetan officials, and saw no Chinese influence in the area.
By signing the Simla Convention with Tibet, the British had violated the Anglo-Russian Convention of 1907, in which both parties were not to negotiate with Tibet, "except through the intermediary of the Chinese Government", as well as the Anglo-Chinese Convention of 1906, which bound the British government "not to annex Tibetan territory". Because of doubts concerning the legal status of the accord, the British did not put the McMahon Line on their maps until 1937, nor did they publish the Simla Convention in the treaty record until 1938. Rejecting Tibet's 1913 declaration of independence, China argued that the Simla Convention and McMahon Line were illegal and that the Tibetan government was merely a local government without treaty-making powers.