The Bloody Hollow is one of a handful of placenames that survive on Ordnance Survey maps as direct, unadorned reminders of what happened across this stretch of undulating bog and pasture on 12th July 1691, when the Battle of Aughrim was fought here. It was the bloodiest engagement of the Williamite War in Ireland, and its geography is still legible in the landscape, if you know what to look for.

The battle unfolded across nine townlands to the east and south of the village of Aughrim. Jacobite forces, commanded by the French general the Marquis de St Ruth, held a strong defensive line along the east-facing slopes of Aughrim Hill, stretching roughly two and a half kilometres from Aughrim Castle in the north down to Attibrassil Bridge in the south. Facing them, the Williamite army under Lieutenant-General Ginkel deployed in a broad arc approximately three kilometres long, running from Melehan Bridge in the north, across Urraghy Hill, and south to Attibrassil and Tristaun, with their artillery positioned across the arc. The Williamites won the day, and the placenames left behind reflect the cost. The Bloody Hollow sits in Kilcommadan townland; Luttrell's Pass, recorded in the neighbouring townland of Coololla, recalls another episode from the fighting. Both names appear on the third edition Ordnance Survey six-inch maps, cartographic fossils embedded in what is otherwise ordinary agricultural ground. Several monuments in the area are also associated specifically with St Ruth, whose death during the battle is said to have broken the Jacobite resistance at a critical moment.