Radcliffe Line in the context of "Partition of Bengal (1947)"

The India–Pakistan border is the international boundary that separates the nations of the Republic of India and the Islamic Republic of Pakistan. At its northern end is the Line of Control, which separates Indian-administered Jammu & Kashmir from Pakistani-administered Kashmir; and at its southern end is Sir Creek, a tidal estuary in the Rann of Kutch between the Indian state of Gujarat and the Pakistani province of Sindh.

Arising from the partition of India in 1947, the border covers the provincial boundaries of Gujarat and Rajasthan with Sindh, and the Radcliffe Line between the partitions of Punjab. It traverses a variety of terrain in the northwestern region of the subcontinent, ranging from major urban areas to inhospitable deserts. Since the beginning of the India–Pakistan conflict shortly after the two countries' conjoined independence, it has been the site of numerous cross-border military standoffs and full-scale wars. The border's total length is 3,323 kilometres (2,065 mi) according to figures given by PBS; it is also ranked as one of the most dangerous international boundaries in the world, based on an article written in Foreign Policy in 2011. During the nighttime, the India–Pakistan border is distinctly visible from outer space due to the 150,000 floodlights installed by India on approximately 50,000 poles.

East Punjab was a province of the Dominion of India from 1947 until 1950. It consist of parts of the Punjab Province of British India that remained in India following the partition of the state between the new dominions of Pakistan and India by the Radcliffe Commission in 1947. The mostly Muslim western parts of the old Punjab became Pakistan's West Punjab, later, renamed as Punjab Province, while the mostly Hindu and Sikh eastern parts remained with India.

India and Pakistan have a complex and largely hostile relationship that is rooted in a multitude of historical and political events, most notably the partition of British India in August 1947.

Two years after World War II, the United Kingdom formally dissolved British India, dividing it into two new sovereign nations: the Union of India and Pakistan. The partitioning of the former British colony resulted in the displacement of up to 15 million people, with the death toll estimated to have reached between several hundred thousand and one million people as Hindus and Muslims migrated in opposite directions across the Radcliffe Line to reach India and Pakistan, respectively. In 1950, India emerged as a secular republic with a Hindu-majority population. Shortly afterwards, in 1956, Pakistan emerged as an Islamic republic with a Muslim-majority population.

Sylhet Division (Sylheti: ꠍꠤꠟꠐ ꠛꠤꠜꠣꠉ, pronounced [sílɔʈ bibáɡ]; Bengali: সিলেট বিভাগ, pronounced [sileʈ bibʱaɡ] ) is a northeastern division of Bangladesh, renowned for its lush tea gardens, rolling hills and vibrant cultural heritage. Covering an area of approximately 12,298 square kilometres, it is bordered by the Indian states of Meghalaya, Assam and Tripura to the north, east and south respectively, while domestically it adjoins Chattogram to the southwest and Dhaka and Mymensingh to the west.

Prior to Partition in 1947, it included Karimganj subdivision (presently in Barak Valley, Assam, India). However, Karimganj (including the thanas of Badarpur, Patharkandi and Ratabari) was inexplicably severed from Sylhet by the Radcliffe Boundary Commission. According to Niharranjan Ray, it was partly due to a plea from a delegation led by Abdul Matlib Mazumdar.

Sikhism is a minority religion in Pakistan with a population of around 16,000 Sikhs, accounting for 0.01% of the national population. Although Sikhs form a small community in Pakistan today, Sikhism has an extensive heritage and history in the country. Sikhism originated from what is now Punjab, Pakistan in the 15th century. By the 18th and 19th centuries, the Sikh community had become a major political power in Punjab, with Sikh leader maharaja Ranjit Singh founding the Sikh Empire which had its capital in Lahore, today the second-largest city in Pakistan. Nankana Sahib, the birthplace of Guru Nanak, the founder of Sikhism, is located in Pakistani Punjab; moreover, Kartarpur Sahib, the place where Guru Nanak died and was subsequently buried, is also located in the same province.

According to the 1941 census, the Sikh population comprised roughly 1.67 million persons or 6.1 percent of the total population in the region that would ultimately become Pakistan, notably concentrated in West Punjab, within the contemporary province of Punjab, Pakistan, where the Sikh population stood at roughly 1.52 million persons or 8.8 percent of the total population. By 1947, it is estimated that the Sikh population had increased to over 2 million persons in the region which became Pakistan with significant populations existing in the largest cities in the Punjab such as Lahore, Rawalpindi and Faisalabad (then Lyallpur). With communal violence and religious cleansing accompanying the Partition of British India at the time, the vast majority departed the region en masse, primarily migrating eastward to the region of Punjab that would fall on the eastern side of the Radcliffe Line and Delhi, with corresponding mass migration of Muslims into Pakistan from India.