The Mellifont Abbey stands as the first Cistercian monastery established in Ireland by St Malachy of Armagh in 1142. With the aid of a small group of monks sent by St Bernard from Clairvaux, the abbey was built, although the monks found it difficult to adapt to life in Ireland and soon returned to France. Despite this, Mellifont Abbey was completed and consecrated with great grandeur, boasting several remarkable architectural features, including the impressive two-storey octagonal lavabo.
In 1152, the monks at Mellifont Abbey hosted a significant synod. While the abbey later fell into private ownership, it continued to play a crucial role in Irish history. The Treaty of Mellifont, which concluded the Nine Years War, was signed here in 1603, and William of Orange used the abbey as his headquarters during the historic Battle of the Boyne.