BIRR or PARSONSTOWN, urban district, Offaly Co. (for merly King's Co.), Ireland, on rising ground on a branch of the Great Southern railway, by which it is 87m. W.S.W. from Dublin. Pop. (1926) 3,391. Cumberland square is the point from which the several principal streets diverge in regular form. There is a fine castle, housing a famous reflecting telescope. Among in stitutions the schools of the Brothers of the Presentation Order are noteworthy. Some trade is carried on in corn and timber and in brewing and distilling.
An abbey was founded at Birr by St. Brendan (d. S73), to whom the present parish church is dedicated. The district formed part of Ely O'Carroll, and was not included in King's Co. till the time of James I. A battle is said to have been fought near Birr in the 3rd century between Cormac, son of Cond, and the people of Munster. The castle was the chief seat of the O'Car rolls. In the reign of James I. it was assigned to Lawrence Par sons. From him the alternative name of the town is derived. The castle was taken by Ireton in 1650. It also suffered assault in 1688 and 169o.