The bilateral relations between Nepal and China are defined by the Sino-Nepalese Treaty of Peace and Friendship signed on April 28, 1960, by the two countries.

[4][5][6] Based on the amount of remittance to Nepal sent by Nepalese migrants working in India (amounting to nearly $1.021 billion per year),[4] the government of Nepal estimate that there are around 1 million Nepalese migrant workers in India as of 2021, while the number of Nepalis in China is minuscule (3,500 in Mainland and 15,950 in Hong Kong)[7] as of 2017.

Around 600–650 CE, Nepalese Princess Bhrikuti (Bal-mo-bza' Khri-btsun in Tibetan) married Songtsän Gampo, the earliest known Emperor of Tibet.

[citation needed] During the Tang dynasty, the Chinese envoy Wang Xuance led an army of Nepalese and Tibetans to defeat an usurper in the Indian Kingdom of Magadha.

[1] Through the tenth quinquennial mission to China (1837), under the leadership of Chautariya Pushkar Shah, the Nepalese government again requested the Daoguang Emperor court to either send troops or a subsidy of Twenty million rupees to oppose the British.

However, the Nepalese delegation was said to have been met with a stern refusal of its petition for monetary support, and instructed by the Qing court to stop further hostilities against the British.

[citation needed] In an attempt to preserve the lucrative coin export business and trade advantages, the Nepalese Kingdom, under the leadership of Jung Bahadur Rana again invaded Tibet in 1855 during the second Nepalese-Tibetan War, and raided the Tashilhunpo Monastery in Shigatse, home to the Panchen Lama at that time.

Nepal's refusal to hand back the control of Tashilhunpo Monastery led to the second Sino-Nepalese War which resulted in a stalemate; a major setback for Tibetans, ultimately culminating into the Treaty of Thapathali on March 24, 1856.

The withdrawal of Nepalese forces from Tibetan areas adjacent to Tibet-Nepal border in 1856 provided the Qing court with the opportunity to firmly tighten its grip in and around Lhasa and throughout Tibet.

[19] During the late 19th century (1899–1901), after the destabilization of Qing Imperial Court due to the Boxer Rebellion, the British Raj as the unchallenged and the dominant power in the sub-continent exerted total control over China's frontier regions including Nepal.

The Buddhist monarchy in The Kingdom of Lo (Upper Mustang), previously a part of the Tibetan Empire but now in Nepal, was terminated only in 2008.

[23] Spinach seeds were first gifted by Narendra Dev, a king of Licchavi Dynasty of Nepal to Emperor Taizong of Tang.

[26] As the strength of the People's Republic of China grew, Nepal developed greater room for diplomatic maneuver.

[26] Soon afterwards, the Sino-Indian war broke out, and Indian losses to China made it unwilling to risk further confrontation with Nepal; India lifted the blockade.

[26] From the early 1960s until 1973, the United States Central Intelligence Agency trained and financed Tibetan guerillas operating in opposition to China from two districts in Nepal.

[1][2][27] When the United States, United Kingdom and India refused to supply arms to the regime of King Gyanendra of Nepal, who had assumed direct rule to suppress the Maoist insurgency during the Nepalese civil war (1996–2006), China responded by dispatching arms to Nepal, in spite of the ideological affinity of the Maoists with China.

[41] Critics have described Nepal's Pokhara Airport and the Trans-Himalayan Multi-dimensional Connectivity Network, as potential "debt traps.

[37] In June 2018, China and Nepal announced an agreement to connect Xigazê, Tibet Autonomous Region with Kathmandu, via a new railroad.

[53][54] Indian media sources also reported that Nepal Agriculture department's documented massive road development projects in the Tibet Autonomous Region that have caused Sumjung, Kam Khola and Arun rivers to change their course and expand China's boundary into northern territories of Nepal, and warned that even more Nepalese land would be encroached by the Chinese if the rivers continue to change course.

Indian media sources also said that China could set up Border Observation Post of Armed Police in these encroached territories.

This was supported by Deputy CDO of Humla and Provincial MLA Jeevan Bahadur Shahi, who collected proofs by making days-long visits and letting them go public.

[64] The government of Nepal tends to deny or downplay any territorial disputes with China for fear of losing economic favors.