1947 Britain divides its Indian empire into secular but mainly Hindu India and Muslim Pakistan, triggering one of the greatest and bloodiest migrations of modern history.

1947/48 India and Pakistan go to their first war over the disputed Himalayan region of Kashmir. The war ended with a UN-ordered ceasefire and resolution, seeking a plebiscite for the people of Jammu and Kashmir to decide whether to become part of India or Pakistan.

1965 India and Pakistan go to war over Kashmir. Fighting ends after United Nations calls for ceasefire.

1971 Pakistan and India go to war a third time over East Pakistan, which became independent Bangladesh.

1972 Pakistani Prime Minister Zulfiqar Ali Bhutto and Indian prime minister Indira Gandhi sign agreement in Simla to lay principles meant to govern relations.

1974 India detonates its first nuclear device.

1990 Indian Army opens fire in Kashmir's summer capital Srinagar during protest against crackdown on separatism, killing 38 and spurring a revolt. India accuses Pakistan of arming and sending Islamist militants into Indian Kashmir.

1998, May India carries out five underground nuclear tests and announces plans to build a nuclear arsenal; Pakistan conducts six tests of its own in response.

1999, Feb Indian Prime Minister Atal Behari Vajpayee makes a historic bus ride to Pakistan for summit with Pakistani counterpart Nawaz Sharif.

May The two countries stand on the brink of their fourth war after India launches major counter-strike against Pakistani intruders dug in on mountains in Kargil in Indian Kashmir. 2000

July Summit between General Pervez Musharraf and Vajpayee in the Indian city of Agra ends in failure.

2001, Dec Militants attack Indian parliament. Fourteen people, including the five assailants, are killed. India blames Pakistan-based Kashmiri separatist groups Lashkar-e-Toiba and Jaish-e-Mohammad and demands action against them.

2003 Pakistan announces ceasefire along the Line of Control, the de facto border in Kashmir. India welcomes the move.

2004 The two countries launch a peace process that brings an improvement in diplomatic, sporting and trade links but no progress on Kashmir. Peace process comes under strain from occasional bomb attacks in India.

2008, July India says Pakistan's ISI intelligence agency was behind a bomb attack on the Indian embassy in Kabul that killed 58 people.

Nov Mumbai attacks bring tension to its highest level since since the weeks following the December 2001 attack on India's Parliament.