Cassidi of Glenbrook

The very ancient Celtic family of Úa Caiside or O'CASSIDY was for ages seated in County Fermanagh, where the village of Ballycassidy preserves the name.Their territory was called Cuil-na-n-Oirear,  the corner or angle of harbours, situated on the eastern shore of Upper Lough Erne, immediately opposite some beautiful islets, whose indentations form the miniature haven that gave the place its title. It became known as the barony of Coole. 

The Úa Caiside were hereditary doctors in medicine, or state physicians of the Maguires, the former chiefs of Fermanagh; and they held their district ex officio, according to the laws of tanistry. In 1541, Roderick Cassidy, Archdeacon of Clogher, eminently versed in the historical records of his country, died. Besides having written part of the Register of Clogher, he also compiled the latter part of the Annals of Ulster. 

Among inquisitions in the Exchequer is one taken at Ballycassidy, County Fermanagh, in 1630, at which time the family had branched out widely in the counties of Fermanagh, Louth, and Monaghan.

To one of these scions we refer

HENRY O'CASSIDY MD, who had followed his ancestral pursuits in medicine, was of Greatwood, Mullaghbawn, and Drumkirk, County Louth, and of various estates in County Monaghan.

He was born ca 1650.

Dr O'Cassidy married and had, with other issue,

FERGUS, his heir;
Edmund, scholar of Trinity College, Dublin, 1710;
Margaret, m Eugene O'Docherty, of Newtown, County Leitrim.

The elder son,

FERGUS O'CASSIDY, of Greatwood, County Louth, and of the townland of Derry, County Monaghan, had two sons, of whom the elder,

PATRICK CASSIDY, of Derry, parish of Magheracloone, near Carrickmacross, espoused Catherine Flood, and had issue.

Mr Cassidy's last will was dated 1753, and proved in 1757.

Among other directions he desired "to be buried in my tombe at Carrick McCross".

His youngest son,

FRANCIS CASSIDY, born ca 1747, of Cashel, County Tipperary, wedded Sarah Magee, a first cousin of the Most Rev William Magee, Lord Archbishop of Dublin, and had issue,

MARK, his heir;
Francis Duff, captain, 60th Rifles; private secretary to Lord Castlereagh;
Francis, died young.

His eldest son,

THE REV MARK CASSIDY (1777-1839), Chancellor of Kilfenora and Incumbent of Newtownards, County Down, ca 1808-39, espoused, in 1808, Henrietta, daughter (and co-heiress with her sister Esther, wife of the Rev Prebendary Cleland) of Samuel Jackson, of Stormount [sic], near Belfast, and had issue,

Samuel, of Glenbrook; m Esther Scott; died childless, 1843;
Charles;
Frederick (Rev), Vicar of Grindon, Co Durham;
William (Rev);
Robert, of Ballyhackamore House, Belfast, m Anne, daughter of Dr Ardagh;
Loftus Tottenham, Lieutenant-Colonel, 18th Hussars;
Alfred;
FRANCIS PETER, of whom hereafter;
Sarah; Henrietta; Fanny; Emily.

Mr Cassidy's youngest son,

FRANCIS PETER CASSIDY JP (1810-79), of Glenbrook, County Londonderry, Colonel, 34th Regiment, married, in 1853, Maria Lucy Anne, daughter of Matthew Hayman, of South Abbey, Youghal, and had issue,

FRANCIS RICHARD, his heir;
Helen Hayman Henrietta;
Mary Mortimer.

Colonel Cassidy served with his regiment during the Indian mutiny, and was severely wounded at the battle of Cawnpore, in 1857.

He was succeeded by his son,

DR FRANCIS RICHARD CASSIDI MBE JP (1858-1939), of Glenbrook, Director of Transport, First Line Hospitals, Derbyshire, in 1st World War, Associate of the Order of St John of Jerusalem, who wedded, in 1887, Marion Elizabeth, daughter of Dr John Duncanson, of Alloa, Clackmannanshire, and had issue,

FRANCIS LAIRD, his heir;
ROBERT ALEXANDER, great-grandfather of Admiral Sir Desmond Cassidi;
Marjorie May, 1888-90.

The elder son,

DR FRANCIS LAIRD CASSIDI VRD (1889-1963), of Glenbrook (which property he made over to his son in 1950), Surgeon Captain RNVR, Honorary Surgeon to HM KING GEORGE VI, married, in 1924, Phyllis Mary, daughter of the Rev A C Haviland, of Lilley Rectory, Hertfordshire, and had issue,

FRANCIS PAUL, his heir;
Oonagh Teresa, served during 2nd World War in WRNS;
Catriona Elspeth, b 1955.

The only son,

DR FRANCIS PAUL CASSIDI TD, of Glenbrook, born in 1925, married, in 1953, Barbara Geraldine, daughter of Major W T Temple RA, of 118, Shorncliffe Road, Folkestone, Kent, had issue,

Francis James, b 1962;
Penelope Jenetta, b 1954;
Alison Ruth, b 1955;
Melian Geraldine, b 1959.

Dr Cassidi graduated from St Thomas Hospital Medical School, London, in 1948, with a Bachelor of Surgery; RMO, 4th Battalion, The Buffs (Territorial Army); major, Royal Army Medical Corps (Territorial Army); Police Surgeon, KCC; Medical Officer at HM Prison, Canterbury, Kent; Territorial Decoration, 1968.

He lived, in 1976, at St Dunstan's House, Canterbury, Kent, and Glenbrook, Magherafelt, County Londonderry, and had issue.

*****

THE younger son of Dr Francis Richard Cassidi (1858-1939), of Glenbrook,

COMMANDER ROBERT ALEXANDER CASSIDI (1894-1966), Royal Navy, of Lingen Grange, Shropshire, was father of

ADMIRAL SIR (ARTHUR) DESMOND CASSIDI GCB (1925-2019), who married, in 1950, Dorothy Sheelagh Marie, daughter of the Rev Canon Robert Francis Scott, of Garvagh, Couny Londonderry, and had issue,

Rory Francis Alexander (b 1958);
Clare Louisa; Rosalind Eileen.

GLENBROOK HOUSE, near Magherafelt, County Londonderry, is a somewhat Gothic, late-Georgian house.

Its entrance is in a three-sided, battlemented bow between two gables with finials and small, overhanging oriels.

The house had become neglected and derelict for a period.

It was completely restored and enhanced in 2013 by Des Ewing Achitects for the new owner.

First published in November, 2013.