The name Ballymascanlan means "town of the son of Scanlan": a reference to Scanlan, son of Fingin, chief of the Ui Méith, who died in 672. The Ui Méith were rulers of the kingdom of Oriel until the Anglo-Norman period. An Ui Meith is credited with having defeated the Danes in Dundalk Bay in 833.from whence, it is believed, the clan motto of 'POG MA THOIN' was first introduced. In 1185, during the Norman-English period, the district of Ballymascanlan as far north as Carrickarnon was donated by Hugh de Lacy to the CistercianAbbey of Mellifont.
Following the dissolution of the monasteries by King Henry VIII the lordship of Ballymascanlan was granted to Sir Edward Moore, ancestor of the Marquis of Drogheda. Sir Garrett Moore inherited the title and estates in 1600 and was a friend of Hugh O'Neill, the Earl of Tyrone, who was a frequent visitor to Mellifont and Ballymascanlon. It remained in the hands of the Moore family until the middle of the 18th century.