The Eastern Command of the Pakistan Army (initially designated as III Corps) was a corps-sized military field manoeuvre formation overseen and commanded by its Commander, typically at the holding rank of the Lieutenant-General.
From the partition of India by Great Britain in 1947 and until 1970, Pakistan was a divided country with consists of two wings geographically separated by 1,000 miles (1,600 km). With chain of command and armed forces' combat machinery stationed in the Western wing, the military mission of the Pakistan armed forces in Eastern wing was to defend and hold in reserves until Pakistani military in west staled or ceasefire with larger Indian Army (in case of war). The Central Command based in Army GHQ in Rawalpindi at that time created the formation with one army commander who was to be assisted by the naval and air commanders. War planners had drawn up a plan to defend Dacca by concentrating all their forces along the Dhaka Bowl (the area surrounded by the rivers Jamuna, Padma and Meghna).