During the First World War , Punjabi manpower contributed heavily to the Indian Army . Out of a total of 683,149 combat troops , 349,688 hailed from the province . In 1918 , an influenza epidemic broke out in the province , resulting in the deaths of an estimated 962,937 people or 4.77 percent of the total estimated population . In March 1919 the Rowlatt Act was passed extending emergency measures of detention and incarceration in response to the perceived threat of terrorism from revolutionary nationalist organisations . This led to the infamous Jallianwala Bagh massacre in April 1919 where the British colonel Reginald Dyer ordered his troops to fire on a group of some 10,000 unarmed protesters and Baisakhi pilgrims
Jallianwala Bagh massacre
Jallianwala Bagh massacre
Punjab Province (British India)