KILLYLEAGH, a market and post-town, and a parish, partly in the barony of CASTLEREAGH, but chiefly in that of DUFFERIN, county of DOWN, and province of ULSTER, 5 miles (N. E.) from Downpatrick, arid 78? (N. by N.) from Dublin, on the mail coach road from Belfast to Downpatrick ; containing 5712 inhabitants, of which number, 1147 are in the town. This place, which is situated on the western shore of Strangford Lough, was a port of some eminence previously to the conquest of Ireland by the English ; and, with the adjoining barony of Kinalearty, formed part of the territories of the native sept of the McCartans. It was afterwards granted to De Courcy, who, in order to protect it from the attacks of that powerful chieftain, erected castles on every advantageous site round the shores of the lake, among which the principal was the Castle of Dufferin. In 1356, Edw. III. appointed John De Mandeville, warden of this castle, which subsequently fell into the hands of the O'Nials, who maintained possession of it till 1561, when the adjoining territory was by Elizabeth granted to Hugo White, who shortly afterwards erected a castle at Killyleagh, into which he removed his warden from Castle Dufferin. Shane O'Nial besieged the newly erected castle in 1567, and meeting with a powerful resistance, set fire to the town ; but a league being subsequently made between the McCartans and the O'Nials, they jointly attacked the castle, dispossessed the family of White, and usurped the uncontrolled dominion of the entire country. On the suppression of the Tyrone rebellion at the close of the 16th century, the possessions of the McCartans were confiscated, and the manor and district of Killyleagh were subsequently granted by Jas. I. to Sir James Hamilton, who restored and considerably enlarged the castle, which, after his elevation to the peerage by the title of Lord Claneboy, he made his principal residence. The castle was besieged and taken by Gen. Monk for the parliament, in 1648, and was partly demolished in the war of that period, but was substantially repaired in 1666, and in it was born Archibald Hamilton Rowan, Esq., whose grandson, a minor, is now the proprietor. It is a large and strong pile of building, in the later English style, occupying an eminence which commands the town, but affords no protection to the harbour.
The town is pleasantly situated on a gentle eminence on the western shore of Strangford lough, and consists of two nearly parallel streets, intersected by a longer street, which forms the principal thoroughfare ; it contains 207 houses, built principally of clay-slate found in the parish, and is the property of Lord Dufferin and Archibald Hamilton, Esq. The cotton manufacture is carried on upon a very extensive scale. Some large mills were built upon a copious stream, in 1824, by Messrs. Martin and Co., and were greatly enlarged in 1828: in these works are 13,798 spindles, employing 186 persons, and 244 power-looms attended by 156 persons, constantly engaged in weaving printers' cloths for the Manchester market ; and connected with this manufactory are more than 2000 hand-looms in the neighbouring districts. The buildings, which are very spacious and six stories high, are lighted with gas made on the premises, and the proprietors have erected a steam-engine of 35 horse power. The trade of the port is limited, and consists principally in the exportation of wheat, barley, oats, potatoes, butter, kelp, and cotton goods ; and in the importation of cotton, wool, coal, iron, salt, and general merchandise. The harbour is well sheltered, and is accessible to vessels not drawing more than 10 feet of water. The quay and basin are very commodious, and were completed in 1833, at an expense of more than #1000, defrayed solely by Lord Dufferin. The market is on Friday, and the fairs are on April 10th, Trinity-Monday, Oct. 11th, and Dec. 11th. A constabulary police force is stationed in the town, and there are barracks for the North Down militia, of which this place is the headquarters. The inhabitants received a charter from Jas. I., in the 10th year of his reign, by which they were incorporated by the designation of the "Provost, Free Burgesses, and Commonalty of the Borough of Killileagh." By this charter the corporation consists of a provost (annually elected), 12 free burgesses, and an indefinite number of freemen, assisted by a town-clerk, two sergeants-at-mace, and other officers, all of whom are chosen by the provost and free burgesses, by whom also freemen are admitted. The corporation, under their charter, continued to return two members to the Irish parliament till the Union, when the borough was disfranchised, and the #15,000 awarded as compensation was paid to Sir James Stevenson Blackwood, Bart., now Lord Dufferin. The court of record for the borough, which had jurisdiction to the extent of five marks, has long been discontinued. The seneschal of the manor, who is appointed by Mr. Hamilton, holds a court every three weeks, for the recovery of debts not exceeding #10, and a courtleet annually ; and a court of petty sessions is held every alternate week.
The parish, according to the Ordnance survey, comprises 11,759? statute acres (including 123? under water), of which 988? are in the barony of Upper Castlereagh, and the remainder in that of Dufferin. The soil is generally fertile and the system of agriculture improved ; there is very little waste land, and the bogs are productive both of turf and of bog fir. There are extensive quarries of basalt and clay-slate, from which has been taken the whole of the stone of which the town is built. The principal seats are Delamont, the residence of R. Gordon, Esq. ; Ringdufferin, of 3. Bailie, Esq. ; Killyleagh Castle, of Mrs. Hamilton ; Tullyvery House, of 3. Heron, Esq. ; Ardigon House, of R. Heron, Esq. ; Shrigley, of 3. Martin, jun., Esq. ; Gosean of A. H. Read, Esq. ; and the handsome residence of the Hon. Hans Blackwood, in the town. The living is a rectory, in the diocese of Down, and in the patronage of the Provost and Fellows of Trinity College, Dublin: the tithes amount to #795. The church, a handsome cruciform structure, with a tower surmounted by a spire of good proportions, was built in 1640, but becoming dilapidated, was rebuilt, and the tower and the spire added, by Lord Dufferin, at an expense of more than #5000, exclusively of a loan of #2000 from the late Board of First Fruits in 1812. It contains some handsome monuments to the Blackwood family, including one to the memory of Capt. Blackwood, who fell at Waterloo ; another to Capt. Blackwood of the North Downshire militia, and a third to the Rev. James Clewlow ; and in the churchyard is the sepulchral vault of the Dufferin family, recently erected, in which Admiral Blackwood was interred, and near it a monument erected by the parishioners to the Rev. Peter Carlton, the late rector. The glebe-house, towards the erection of which, in 1815, the late Board of First Fruits contributed a gift of #100 and a loan of #1350, is a very handsome residence ; the glebe comprises 14 acres. In the R. C. divisions the parish forms part of the union or district of Kilmore: the chapel, a small neat building, was erected in 1832. There is a place of worship for Presbyterians in connection with the Synod of Ulster, of the first class. About 450 children are taught in six public schools, of which three were built and are supported by Lord and Lady Dufferin, D. Gordon, Esq., and the Rev. A. R. Hamilton ; and there are four private schools, in which are about 140 children, and three Sunday schools. The remains of the ancient parish church are still visible in a low marshy meadow to the north-west of the town: the eastern gable, perforated with two narrow lancet shaped windows, is yet standing. Sir Hans Sloane, the celebrated physician and naturalist, was born here in 1660. The barony, of which this place is the head, gives the title of Baron to the family of Blackwood, Barons of Dufferin and Claneboy.