Despite the initial military failure of the UnitedIrish rebellion in Kildare, the consolidation of Government forces in Naas and the priority given to the effort to crush the raging rebellion in County Wexford, meant that much of the county remained in rebel hands since the outbreak of the rebellion. Towns such as Prosperous and Clane were in rebel hands, while towns such as Maynooth, Kilcock and Kildare town had been attacked and briefly occupied by the rebels. By 19 June however, neighbouring County Meath had been judged sufficiently pacified to allow for troops to be sent from there into Kildare to retake the rebel-held territory. A force of 400 troops, with two pieces of artillery, was sent out from Trim on 18 June to locate and destroy the rebel army led by William Aylmer. When Alymer received news of the offensive, he decided to rally his forces and engage the approaching military head-on, choosing to fight at Ovidstown Hill, about three miles south-west of Kilcock. On the eve before the battle, the Irish rebels received word from an anonymous source that the wine cellar of the empty Hortland House was left open. Rebels were sent to the house where they ransacked the basement and brought all the alcohol back to camp. It is understood that the majority of the Irish rebels entered battle under the influence of alcohol and this is said to be one of the main reasons for the rebels failure at Ovidstown.
Battle
Almost 4,000 rebels had gathered by the time approaching British troops were spotted, and they began to deploy behind ditches on both sides of the road in an attempt to ambush the approaching military. The manoeuvre failed when light infantry deployed along both rebel flanks, and drove them back with their superior firepower. Despite this success, the British were unable to organise their cavalry in time to pursue the retreating rebels across the broken terrain and were also experiencing difficulties in deploying their artillery. Trying to take advantage of the respite, Alymer ordered his men to charge the encumbered soldiers before they could complete their deployments but the charge petered out as the rebels hesitated and merely occupied a facing position covered by hedges. This gave the British artillery enough time to fire rounds of grapeshot into the massed rebels who were now forced to come out from their positions and were subsequently exposed to volleys of musket fire from the infantry. Forced back onto the offensive, the rebels charged again, reaching the British lines and almost seizing the artillery, but they had left their left flank unprotected which gave the cavalry the opportunity to launch a counter-attack which broke and routed the rebel attack.
Aftermath
The rebels lost about 200 men while the military lost 25, Alymer was forced to relocate his remaining forces to the protection of the Bog of Allen where they later linked up with survivors of the Wexford rebellion under Anthony Perry. The British followed up their victory, pursuing and killing the fleeing rebels, and retaking and sacking the town of Prosperous, held by rebels since the Battle of Prosperous.
