A grange was originally an area of land in Ireland some miles away from an urban-based monastery where in mediæval times food was grown for the monastery. Though initially just a description of the area of land used for food production, the word 'Grange' often evolved into the name of the townland or parish, replacing an earlier name. Most Irish counties have a place called 'Grange'; some have a number.

Example

In the eleventh century St. Mary's Abbey in Navan, County Meath was supplied with food by a number of granges, including one located at Killenagolach, near the ancient bishopric of Ardbraccan (modern day 'Bohermeen'), five miles from the town. Eventually 'Grange' replaced Killenagolach as name of the local townland and parish, and has remained the name of the area ever since.

Other Granges

Grange, County Sligo - birthplace of Lola Montez
Patrons of Husbandry, the Grange movement in the United States