Kilsallagh (from Irish: Coill Salach meaning 'Muddy or Boggy Wood') is a townland in the civil parish of Templeport, County Cavan, Ireland. It lies in the Roman Catholic parish of Templeport and barony of Tullyhaw.
Kilsallagh is bounded on the north by Killycrin townland, on the west by Muinaghan and Port, Templeport townlands, on the south by Cor, Templeport townland and on the east by Keenagh, Templeport, Munlough North and Killywaum townlands. Its chief geographical features are two streams, some spring wells and dug wells. The Ordnance Survey Namebooks for 1836 state- The soil is of a light yellow clay, intermixed with boulders of freestone.
Kilsallagh is traversed by the regional N87 road (Ireland), minor roads and rural lanes. The crossroads named Father Terence's Cross was named after the nearby residence of the local Roman Catholic curate at the time, Terence Magauran, who was curate of Templeport parish from 1849 to 1877 and later parish priest from 1877 to 1896.
The townland covers 169 statute acres.
Until the 19th century, the modern townland of Killywaum formed a sub-division of Kilsallagh.
The 1609 Baronial Map depicts the townland as Kilsallagh.
The 1652 Commonwealth Survey lists the townland as Kilsallagh.
An 1809 map of the ecclesiastical lands in Templeport depicts it as Kilsoldagh, with a sub-division on the north-east entitled Gortinawaghey.
On 19 January 1586 Queen Elizabeth I of England granted a pardon (No. 4813) to Ferriell M'Manus M'Thomas Magawran of Killsollaghe for fighting against the Queen's forces. The said Farrell McGovern was the grandson of Tomas Mág Samhradháin who was chief of the McGovern Clan from 1512 to 1532.