Soon after the War, the Army HQ in Pakistan ordered all the formations and units of the Pakistan Army to destroy their respective war diaries.(Source) Hence, the Indian version shall be the main source of my briefing. In case anyone of you comes across any credible source for the Pakistani version, kindly pass them on. In the meantime, I shall try to put forward the Pakistani version from wherever I can. But at the end of the day, I am an Indian, and it might not be as unbiased as I want.
Background
India and Pakistan, both had been claiming Kashmir ever since 1947. But since ceasefire in 1948, there had been no military conflict between the two nations. Meanwhile Pakistan pursued to internationalize Kashmir and tried its best through diplomacy. In 1962, India suffered a crushing and humiliating defeat at the hands of Chinese. Pakistanis now began to believe that India could be militarily defeated.
India had not invested much in defense up until 1962. But things began to change as India started investing in defense. It also got some defense aid from US and UK in the form weapons who were alarmed at the rise of communist China.
Meanwhile, Pakistan had invested and modernized its defense forces. Moreover, being a part of US led millitary alliances SEATO and CENTO, it got access to the latest weapons. In 1963, Pakistan ceded Aksai-Chin to China and thus began a friendship which had a common enemy, India.
Integration of Kashmir with India
It must be noted that Jammu & Kashmir had not been fully integrated with India. Article 370 guarantees a special status to the State. Under this, Indian Parliament had limited rights over the State Govt. and citizens of India outside Kashmir cannot buy property in the state. Nehru successor Shastri was trying to integrate the state. This made the Pakistanis nervous.
Pandit Jawhar Lal Nehru's successor Lal Bahadur Shastri, rushed through a series of "Constitutional amendments, ( Articles 356 and 357 of the Indian Constitution ) despite strong opposition." The aim was to bring the State of Jammu and Kashmir in line with other States of the Indian Union. The head of the State under new law was not to be elected by the State Legislature, rather the Delhi government had a right to nominate anyone. Also under the new law four seats were allocated in the Indian Parliament, Lok Sabha, to the State of Jammu and Kashmir. And for the first time the Kashmiri people would contest for seats in the Indian Parliament. This really meant a gradual erosion of the Article 370 which gave special status to Kashmir. There was a strong reaction to this in the Valley. Sheikh Abdullah declared on May 7 1964, that ‘no solution will be lasting unless it has the approval of all the parties concerned, namely India, Pakistan and the people of Kashmir’. (Source)Objectives
India and Pakistan had two completely different objectives for the war.
With India trying to integrate J&K with itself and increasing defense expenditure, Pakistan felt nervous. They saw that this was their chance to attack India (at a time when it was weakened by the 1962 War), and take Kashmir, something they haven't been able to achieve diplomatically.
On the other hand, Indian objectives were rather defensive. India sought to maintain status quo of Kashmir. It also didn't want to escalate the conflict too much.
I shall analyze at the end where things stood at the end of the war and were objectives of the two sides met.
Pre-War Clashes in Rann of Kutch
Skirmishes at the Rann of Kutch flared up almost accidentally in the Spring of 1965, and India and Pakistan found themselves drawn into the first of their two undeclared wars.
The dispute goes back to the days of the British rule in India. The Rann was the bone of contention between the princely state Kutch, and the British Indian province of Sindh. When British India was partitioned, Kutch acceded to India and Sindh to Pakistan. The issue was inherited by these two states along some 3,500 sq. miles of territory.
It is important to understand the terrain to region first. The Rann is a Salt Wasteland. It is a sparsely populated area and does not have enough water. Prior to the clashes in 1965, the area was under India control. Northern portion of the Rann was easily accessible from the Sind(Pakistan) as their were roads available leading upto the Rann. The India side wasn't well connected with roads.
Communications also favoured the Pakistanis as Indian Administrative base was located at Bhuj, 177 km away the border. Badin, a sizable town equipped with an airstrip and radar was available only 30 kms from the border. Thus maintainance of border posts was easier for Pakistan than for India.
The conflict started after an increasing number of Pakistani intrusions took place. Indians established a new post closer to the border called Sardar Post and Pakistanis retaliated by also having a new post. India also carried on a joint exercise of the Army and Navy called Arrow Head in the region. This alarmed the Pakistanis. In early April, Pakistan attacked the Sardar post and thus began the conflict in the Rann of Kutch. The conflict ended on 28th April when British Prime Minister Harold Wilson convinced the two sides for a ceasefire. A tribunal was setup to look into the issue. This tribunal later gave 350 sq. miles of territory out of the total of 3500 to Pakistan.
As far as the conflict in Kutch, India forces suffered a defeat at the hands of the Pakistanis. Despite getting intelligence about the Pakistani troop movements, the India effort was largely uncoordinated. I will quote from the Official History, "For India, Kutch was wrong war with the right enemy at the wrong place. For Pakistan, it was a victorious war out of which it learnt the wrong lesson that it could win a cakewalk victory in Kashmir".
Kargil Operations
In May, 1965 after defeating India in the Kutch, Pakistanis increased their activities in the Kashmir along the CFL( Ceasefire Line). From what appears, it seems that atleast a part of Kargil (if not all) was under Pakistani control in 1965. As during the 1999 Kargil Conflict, Pakistanis shelled at the Srinagar-Leh highway the only supplyline for Ladakh.
Indian Army decided to take on the enemy and to inflict maximum damage. It was planned to capture certain strategic peaks in Kargil. The situation and tactics used in 1965 weren't quite different from 1999. The terrain was extremely difficult, the temperature were sub-zero and the enemy at a height had an advantage. Indian Army choose to attack through the more difficult approaches to these mountains. This was the first counter-offensive operations taken by the Army in many years.
The operations were extremely successful and Indian captured some of the importants areas like Pt 13620, Black Rocks and Kala Pahar. However, the hard fought areas were given up on June 30 after a solemn assurance by the UN Secretary General about the safety of the Srinagar-Leh route.
Conclusion
Pakistan came out victorious in Round 1 in Kutch while Indians won the Round 2 in Kargil. However, it must be noted that Pakistan had a advantage of the terrain in their favour on both occassions. On both occasions, it was the international community that played a crucial role is de-escalating the conflict. In the next part we shall look in the events of the actual war.