The Battle of Badli-ki-Serai was fought early in the Indian rebellion of 1857, or First War of Indian Independence as it has since been termed in Indian histories of the events. A British and Gurkha force defeated a force of sepoys who had rebelled against the British East India Company. The British victory allowed them to besiege and ultimately capture Delhi.
The revolt occurred on May 10 at Meerut, 60 miles north-west of Delhi. After killing many of their British officers and some civilians, three regiments of Bengal infantry and cavalry marched to Delhi. When they arrived on May 11, they called on the three Bengal infantry regiments there to join them, and for the Moghul King, Bahadur Shah II to lead them. By the end of the day, Delhi was in rebel hands, and news of the rebellion was spreading rapidly over northern India.
Another small British force was advancing from Meerut to meet Anson. It was commanded by Major General W. Hewitt, whose health had been broken by his age and many years' service in India. He eventually had to hand over command to Brigadier Archdale Wilson.
On May 30, some Indian forces from Delhi attacked Wilson's force at the River Hindon. Wilson's infantry, the 60th Rifles, made good use of their Enfield rifles to drive the Indians from the field and capture five light guns. The rebels tried another attack the next day and were again driven back, though they lost no more of their artillery.
The rebel sepoy regiments had dug in at Badli-ki-Serai to oppose their advance. Their strength was estimated in some works as 30,000, but was put closer to 4,000 by historian A.H. Amin. It is of course possible that the sepoy regiments were accompanied onto the battlefield by irregular contingents from Delhi, and scavengers and sight-seers, making effective numbers difficult to estimate.
The rebels' right flank, with most of their artillery, occupied a serai (a walled enclosure) and a village, also surrounded by a wall. Their left flank consisted of a "sandbagged" battery. Both flanks were supposedly protected also by areas of marshy ground. On the left however, there was a gap of a mile between the end of the swamp and the Western Jumna canal, which was not defended. The right flank was similarly vulnerable.
When the British advanced against this position early on June 8, they suffered heavy casualties from the rebel artillery, which was heavier than most of the British guns and very well-handled. Barnard sent his cavalry under Colonel James Hope Grant to outflank the rebel left and a brigade of infantry under Colonel Graves (temporarily replacing Brigadier Jones, who was ill) around the rebel right. As these forces began to threaten the enemy flanks and rear, Barnard ordered his other brigade under Colonel Showers (which included a Gurkha regiment) to charge and capture the enemy artillery with the bayonet. There was severe fighting for the village and serai, but the rebels fled to avoid being surrounded, abandoning thirteen guns.
The sepoys retreated to Delhi in disorder, and some of the citizens thought that the British would follow close on their heels and capture the city before resistance could be organised. The British were too exhausted by the heat and their exertions, and contented themselves with occupying Delhi Ridge north of the city. This led to a costly siege lasting three and a half months, but the city was eventually stormed and the rebels were defeated.
The sepoys' officers had attained rank by seniority only, and none of them proved to be gifted generals, as opposed to platoon commanders. At Badli-ki-Serai, they deployed no forces to protect against outflanking moves, and left themselves no reserves. The sepoys refused to use the Enfield rifle (for which they lacked ammunition in any case), and were forced to use the Brown Bess, which was much less accurate than the Enfield rifle. (Some of the British units at Badli-ki-Serai also had the Brown Bess, but the weapon's short range and inaccuracy hampered the defenders more than the attackers.)