While both countries established full diplomatic ties shortly after their formal independence, their relationship was quickly overshadowed by the mutual effects of the partition as well as by the emergence of conflicting territorial claims over various princely states, with the most significant dispute being that of Jammu and Kashmir.

This geography meant that Pakistan absorbed more Persian and Muslim influences than the rest of the subcontinent, which can be seen in its modern-day usage of a modified Perso-Arabic alphabet for Urdu (see also: Northwestern South Asia).

Pakistan refused to accept the state's accession to India and escalated the conflict, by giving full-fledged support to the rebels and invading tribes.

Pakistan organised the rebel fighting forces of Azad Kashmir into a full-fledged military of 32 battalions, and India insisted that it should be disbanded as part of the demilitarisation.

[20][21] The Indo-Pakistani War of 1965 started following the culmination of skirmishes that took place between April 1965 and September 1965 and Pakistan's Operation Gibraltar, which was designed to infiltrate forces into Jammu and Kashmir to precipitate an insurgency against rule by India.

[26] In 1949, India recorded close to 1 million Hindu refugees, who flooded into West Bengal and other states from East Pakistan (now Bangladesh), owing to communal violence, intimidation and repression from authorities.

While not ruling out war, Prime Minister Nehru and Sardar Patel invited Liaquat Ali Khan for talks in Delhi.

Steadily, hundreds of thousands of Hindus returned to East Pakistan, but the thaw in relations did not last long, primarily owing to the Kashmir conflict.

According to some reports published by the Council of Foreign Relations, the Pakistan military and the ISI have provided covert support to terrorist groups active in Kashmir, including the al-Qaeda affiliate Jaish-e-Mohammed.

Journalist Stephen Suleyman Schwartz notes that several militant and criminal groups are "backed by senior officers in the Pakistani army, the country's ISI intelligence establishment and other armed bodies of the state.

Under intense media pressure, New Delhi complied with the hijackers' demand and freed Maulana Masood Azhar from its captivity in return for the freedom of the Indian passengers on the flight.

The terrorists successfully breached the security cover around the Red Fort and opened fire at the Indian military personnel on duty killing two of them on spot.

[38] Only two months later, two Kashmiri terrorists belonging to Jaish-e-Mohammed raided the Swami Narayan temple complex in Ahmedabad, Gujarat killing 30 people, including 18 women and five children.

[8] Two car bombs exploded in south Mumbai on 25 August 2003; one near the Gateway of India and the other at the famous Zaveri Bazaar, killing at least 48 and injuring 150 people.

Though no terrorist group claimed responsibility for the attacks, Mumbai Police and RAW suspected Lashkar-e-Toiba's hand in the twin blasts.

[51] In May 2010, an Indian court convicted him on four counts of murder, waging war against India, conspiracy and terrorism offences, and sentenced him to death.

[60] Decisions on the development of nuclear weapons were made by Indian political leaders after the Chinese invasion and territorial annexation of North India.

[64] Over the next several years, Pakistan expanded and modernised nuclear power projects around the country to supply its electricity sector and to provide back-up support and benefit to its national economy.

They signed the Shimla Agreement, by which India would return all Pakistani personnel (over 90,000) and captured territory in the west, and the two countries would "settle their differences by peaceful means through bilateral negotiations."

India maintains that the entire former princely state is an integral part of the Indian union, while Pakistan insists that UN resolutions calling for self-determination of the people of the state/province must be taken into account.

There are two main reasons for this: warming of relations between New Delhi and Islamabad which consequently lead to a ceasefire between the two countries in 2003 and the fencing of the Line of Control being carried out by the Indian Army.

A major clash between Indian security forces and militants occurred when a group of insurgents tried to infiltrate into Kashmir from Pakistan in July 2005.

An Indian man held in Pakistani prisons since 1975 as an accused spy walked across the border to freedom 3 March 2008, an unconditional release that Pakistan said was done to improve relations between the two countries.

[79] On 7 September 2012, Indian External Affairs Minister S. M. Krishna would pay 3-day visit to Pakistan to review the progress of bilateral dialogue with his Pakistani counterpart.

[84] On 25 February 2021, India and Pakistan issued a joint statement indicating that both sides agreed to stop firing at each other at the Line of Control (LOC, disputed de facto border) in Kashmir.

[85] Despite this, in July 2021 Indian government rejected Pakistan's call for talks, stating that "Peace, prosperity can't coexist with terrorism".

Aman ki Asha is a joint venture and campaign between The Times of India and the Jang Group calling for mutual peace and development of diplomatic and cultural relations.

Each evening, the Wagah-Attari border ceremony takes place, in which the flags are lowered and guards on both sides make a pompous military display and exchange handshakes.

Hindustani is also widely understood and used as a lingua franca amongst South Asians including Sri Lankans, Nepalis and Bangladeshis, and is the language of Bollywood, which is enjoyed throughout much of the subcontinent.

[104] In tennis, Rohan Bopanna of India and Aisam-ul-Haq Qureshi of Pakistan have formed a successful duo and have been dubbed as the "Indo-Pak Express".