Another website convoluting the Costello origin but with lots of fun info and distant Irish Costello relatives

Copied and pasted from HERE Costello - MacCostello, Charlestown in Co. Mayo

This family are of Cambro (Welsh)-Norman descent, from the family of Gilbert DeAngulo. The name was later Gilbert N'angle, who participated in the Norman invasion of Ireland, (1167-1172 AD), with Richard deClare (Strongbow). Gilbert had two sons, Jocelyn and Costilo, and the son of the latter, known as MacOisdeaibh, (Gaelic son of Costilo) participated in the Norman invasion of Connaught in 1235, along with the deBurgos, (Burkes), and the deLacys, established the Barony of MacOisdeaibh, later MacCostello, in eastern Mayo and western Roscommon, which lasted some four hundred years.

The Costello's were the first of the great Norman families in Ireland to use the "Mac" (Son of) prefix to their name. Like many other Cambro-Norman families they became "More Irish than the Irish themselves". The Barony of MacCostello is still an identifiable geopolitical district in Mayo to this day and the Costello name is very common in Mayo.

Charlestown is very much part of this Barony.

For information on the above, thanks to Bob Costello.

As an addendum to the Costello saga, the following may be of interest relative to the place where the Romantic Tomas Laidir MacCostello was murdered. One day in 1934 when teaching in Tavneena National School, the Principal, Mr Gerry Henry asked me, Delia Henry, if I knew where "Sithestin" west of Swinford was? Although I lived in Killaturley, Swinford was our postal and Market town and I went to Secondary School there, I had never heard of that place and I said I would find out if it existed.

An elderly neighbour of ours, The Lenihans, one Luke Tunney visited in our house. He was about seventy years of age at the time. On his next visit, I put the question to him, was there a village named Sithestin, west of Swinford. After a few moments, he said no, and I quote his own words "There is no Sithestin, but Sithestin Dubhaltaigh" now known as Barcul. It is situated between Shammer Cross roads and the Charlestown/Ballyhaunis road. I had never heard of the word "Dubhaltagh" before, but I cycled through Barcul many times.

The next day I repeated the statement made by Luke Tunney. The Principal got a book called "The Love songs of Connaught" by Douglas Hyde and there in the print was "Sisthestin a Dubhaltaigh" "Dudley's Sithestin". The poem Una Bhain, composed by Tomas Laidir MacCostello, about his lost love, Una McDermott, was on page 117 and underneath it was an account of the place where he was murdered by the Dillons.

The Descendents of The Costellos in the Charlestown area owned some two hundred acres of land at one time, and their Tomb is in Tample graveyard,with the following inscription on it.

"Gloria in Excelsis"
O Lord have mercy on the soul of Thomas Costello Esq, of Hagfield,who departed this life, February the 1st, 1822, aged 95 years, also his wife, Maria Costello, who departed this life, 6th of January 1810, aged 75 years. His son Thomas Costello Esq, who departed this life, August 1st, 1828, aged 78 years. His son Edward Costello Esq, who departed this life, the 2nd of August 1811,aged 59 years. His son Richard Costello Esq, who departed this life, the 1st of September 1859 aged 95 years, and his grand-daughter Louise Costello, who departed this life, on the 10th of June, 1860, aged 19 years. Erected by Peter Costello Esq.
Also buried in this Tomb are the following Descendents: Frances Wynne, nee Costello, wife of Andrew Wynne. Margaret Mulligan, nee Wynne,who was buried on the 16th of February 1987 By her son James,"Seamus" Mulligan.

The Descendents of the Costello family named above still live in the Charlestown area. They are: James "Seamus" Mulligan, his nephew Michael Giblin, Nieces Marcella McBrien, Patricia Leonard, Aclare, Evelyn O'Keefe, and Jacqueline Cummins, Swinford.

Maire McDonnell-Garvey in her Book, 'Mid Connacht', gives a very interesting and detailed account of the Costello Era, and the transition of their lands to the Dillons. In chapter six, the great work done by Charles Strickland - Chairman of Gallen and Costello relief committee - for the relief of the poor during the Famine years, deserves the credit given to it. However, though not mentioned in this account, his greatest achievement must be the founding of the town of Charlestown, where the first house was built in 1846, also, the foundation of the Catholic Church was laid in 1856, and the first Mass was celebrated there in 1858.

The Church and Town in the Parish of Kilebeagh, in the Barony of Costello, have much to be grateful for the work done by Lord Dillon's agent, Charles Strickland.

Dudley Costello, father of Tomas Laidir McCostello, himself suffered at the hands of the Dillons. In 1667 he was killed by Captain Theobald Dillon at Tumgesh, a ford on the River Moy. Captain Dillon and a large number of soldiers, ambushed Dudley and his men.

Dudley Costello and his men were returning from a raid on a planted estate at Cruachan Gailing in the Parish of Killasser, when they were ambushed. Captain Dillon regarded Dudley as the "Scourge of Mayo".

Lament for Dudley Costello.

No more will Barnalyra Wood,
Hear through it's dale and glade
The echoes of the Colonel's voice
Nor his feared Toledo Blade
From Ancient Mask to Regal Erne,
Where with Nangle he ranged wide,
To rob the rich and help the poor
And stem the crimson tide.


So rest in peace bold swordsman
Though no stone marks your grave
For on the gibbet you were hung
Spiked by an Ormond Knave.
But tonight around ruined Castlemore
A Connaught wind will blow
For to praise the name of the one they called
"The Scourge of Old Mayo"