The area was part of Conmaícne Maigh Nissi from the Early Middle Ages. The Reynolds were chiefs of an area comprising much of the baronies of Mohill and Leitrim, then known as Muinter Eolais. the population of Leitrim Barony was.
Museum artefacts
There are a number of medieval artifacts from Leitrim barony preserved in a collection at the Royal Irish Academy museum in Dublin. Weapons include a medieval spear-head found at Corryolus townland beside the River Shannon presents as leaf shaped and made of a bright yellow metal. Another found in the River Shannon at Carrick on Shannon is a perfect and rare form of leaf-shaped spear measuring long by across the middle of the blade. A medieval plain bronze tube found beside Cornacorroo townland, near Jamestown, County Leitrim, probably formed the ferule-end of a spear, measuring in length, is closed at the small extremity, and imperfect on the other. On the same townland, a sword blade was found in 1845 on the bed of the River Shannon, presenting as a small, perfect rapier blade, with large rivet notches, measuring long by in width. Also discovered was a medieval brooch, and a bronze pan measuring wide by deep, much worn on the bottom, has been created from a single place or metal hammered into shape. Domestic household items include a medieval spoon found in 1847 on the bed of the River Shannon, at Gross's island near Carrick on Shannon measures in length, and across the bowl, has an inverted lip prolonged into a T-shaped flange running around the handle for added strength; the metal is paper-thin so was probably not cast in a mould, although it bears traces of hammering. A vessel filled with coins was found in the 19th century under a mound on Sheemore hill was formed of thin sheet brass, imperfect and originally from two pieces, the bottom, the side and lip, patched with rivets, and measuring high by wide.
In the 19th Century the skull of an ancient Irish elk was found in the townland of Kilnagross, parish of Kiltoghert, barony and county of Leitrim, district of Eslin. It is a good specimen, very dark in colour, and lacking the horn on the right and partly on the left side. In a separate find, the upper portion of the head and horn-beam of a small ancient Irish elk was found in the Shannon at Drumsna Bridge, on 19 June 1846.. Both are held by the Royal Irish Academy museum in Dublin.
