The Eastern Command of the Pakistan Army also known as "III Corps" was a corps-sized military formation headed by a lieutenant-general, who was designated the Commander 3 Corps. After the partition of India by United Kingdom, the Islamic Republic of Pakistan was divided into two territories separated by (prior to the independence of Bangladesh in 1971). Most of the assets of the Pakistan armed forces were stationed in West Pakistan; the role of the Pakistan armed forces in East Pakistan was to hold that part of the country until the Pakistani forces defeated India in the west (in case of war). The Pakistan Army created the Eastern Command, with one commander in the rank of Lieutenant General responsible for the command. The armed forces (particularly the Pakistan Army), had drawn up a plan to defend Dhaka by concentrating all their forces along the Dhaka Bowl (the area surrounded by the rivers Jamuna, Padma and Meghna).
After Pakistan launched Operation Searchlight and Operation Barisal to curb the Awami League-led political movement in March 1971 (leading to the creation of Mukti Bahini and insurgency throughout Bangladesh), Lieutenant General A. A. K. Niazi (last commander of 3 Corps) revised the existing plan according to the Pakistan Army's General Headquarters (GHQ) directive (which emphasized the need to prevent the Mukti Bahini from occupying any area of the province and to fight for every inch of territory). HQ expected the Indians to occupy a large area of the province, transfer the Mukti Bahini and Bengali refugees there and recognize the Bangladesh government in exile – turning the insurgency into an international diplomatic issue. Lieutenant General Niazi designated 10 cities (Jessore, Jhenaidah, Bogra, Rangpur, Jamalpur, Mymensingh, Sylhet, Comilla and Chittagong) on major communication hubs as "fortress towns" and placed the bulk of his troops near the Indian border. The final plan called for the armed forces to delay Indian attacks at the border and then gradually fall back to the fortress towns. From the fortresses, part of the surviving force was to take up positions near Dhaka and hold out until India was defeated in the west; Pakistani forces in the fortress towns would delay the bulk of the Indian forces and prevent them from concentrating on Dhaka.
Background
The Pakistan Army inherited six infantry divisions and an armored brigade after independence in 1947 from the British Indian Army, deploying most of their armed assets in West Pakistan. East Pakistan had one infantry brigade in 1948, which was made up of two infantry battalions, the 1st East Bengal Regiment and the 1/14th (1st battalion of 14th Punjab Regiment) or 3/8th Punjab Regiment (3rd battalion of the 8th Punjab Regiment). Between them, the two battalions boasted five rifle companies (a battalion normally had five companies). This weak brigade – under the command of Brigadier Ayub Khan (served as an acting Major General – appointment: GOC, 14th Infantry Division) – and a number of East Pakistan Rifles (EPR) wings were tasked with defending East Pakistan during the Kashmir War of 1947. The Pakistan Air Force (PAF) and Pakistan Navy had little presence in East Pakistan at that time. The reasons for placing more than 90 percent of the armed might in West Pakistan were: West Pakistan borders Kashmir (an issue the Pakistani government was not above using armed force to resolve): Pakistan did not have the economic base to support adequate forces in both wings, and West Pakistan had more strategic relevance than East Pakistan. Most government officials were from West Pakistan or non-Bengali. Most economic development was taking place in West Pakistan, and the bulk of the armed forces was placed there to keep its power base secure. Pakistani military staff planners proposed the following doctrine to justify this deployment: "The defense of the East lies in the West". Broadly speaking, this translated into Pakistan defeating India in the west, regardless of what transpired in the east (including Indian occupation of East Pakistan) because the presumed West Pakistani success would force India to negotiate a favorable settlement. The Pakistani staff also believed in the martial race theory; it was widely believed that one Pakistani soldier was equal to four to ten Hindus/Indian soldiers, and that the numerical superiority of the Indian armed forces could be negated by a smaller number of Pakistani soldiers.