Dempsey Surname Meaning, History & Origin

Select Dempsey Meaning
is an anglicized version of O’Dempsey, the ancestor of
O’Diomsaigh. This family name came from the Gaelic word diomusach, meaning “proud” or
“haughty.” The O’Diomsaighs originated in the territory known as
Clanmalier, on the borders of what are now the Laois and Offaly
counties in Ireland.

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Dempsey Ancestry

The Annals of the Four Masters
recorded in 1193 the death of Dermot O’Dempsey, son of Cubgogda.
He was Chief of Clanmalier, for a long time Lord of Offaly, and the
founder of the Cistercian abbey at Monasterevan in county
Kildare. He also led the Leinster resistance against the
Anglo-Norman invasion in the 1170’s under Strongbow and defeated him in

The O’Dempsey territory, known as Clann Mhaoilughra, comprised a vast
area on both sides of the Barrow river and included the baronies of
Philipstown in Offaly, Portnahinch in Laios, and West Offaly in
Kildare. Lea
in Portnahinch, often occupied by the O’Dempseys, lay
in the center of these lands. Successive
O’Dempsey clan chiefs
held onto their territory.

the 16th
century, the O’Dempseys were on friendly terms with the English,
fighting with them in their attacks on the Irish clans at Mullamast in
1577, and their estates escaped confiscation. Terence O’Dempsey
was knighted in 1599 and created Viscount Clanmalier in 1631.

The O’Dempseys then switched sides. Three of their number were
prominent members of the Confederation of Kilkenny during Cromwellian
times. Loyalty to the Catholic King James II then resulted in the
forfeiture of all their lands in 1691. O’Dempseys had been
prominent in the Battle of the Boyne. Many O’Dempseys were
evicted from their homes and driven into neighboring counties such as
Tipperary. As one English commentator noted:

“Viscount Clanmalier was head of this
family at the Revolution of 1688. They are now obscure and sunk
into poverty and degradation.”

This clan history has most recently been recorded in Patrick Goode’s
2008 book The O’Dempsey Chronicles.

The Dempsey name is still strong in Laois and Offaly,
particularly in
their own homeland, but it has also spread throughout
Ireland. It
is quite common in county Antrim in Ulster where it may be an Irish
version of the Scottish name Dempster. There were a number of
Presbyterian farming families called Dempsey in the parishes of north
Antrim in the 19th century.

After the confiscation of the Clanmalier lands in
1691, Terence O’Dempsey left Ireland and settled in Cheshire. A
descendant of this line was General Sir Miles Dempsey, a commander of
the British Second Army during the D-Day landings in 1944.

James and Ann Dempsey were married in Liverpool in 1821 and James was a
timber merchant.

“The anecdotal account was that the
Dempsey family emanated from Ireland and that the daughters of James
and Ann were known as ‘the Dempsey beauties.'”

These Dempseys were part of a close-knit coterie of Liverpool merchant
families which often intermarried. Daughter Ann Dempsey married the
shipowner Thomas Holderness, daughter Frances the merchant William
Tarbet, daughter Louisa the Liverpool MP John Torr, and daughter Maria
the banker John Smith.

Many Dempseys came from Ireland to industrial Lancashire in the second
half of the 19th century, in search of jobs.

America. The earliest
Dempsey arrival in America was probably William Dempsey who came to
Philadelphia in 1726
as a young boy and made his home in
Virginia. Barnet Dempsey from county
Kildare came to Spartanburg, South Carolina sometime in the
1780’s. His son Levi moved onto Georgia.

Captain Michael
Dempsey, who emigrated to America in the 1830’s, was
from Lea parish in Laois and believed to be related to the Dempseys of
He enlisted in the US Army, fought in Florida in the Seminole Indian
War, and ended up farming in Catahoula parish, Louisiana.

More Dempseys arrived later in the 19th century via ports in the
northeast. Among them were:

  • Michael Dempsey and his sisters from Dublin onboard the Mount Washington to Boston in
    1849. They settled in the Boston area.
  • Lawrence Dempsey from Wexford onboard the Monongahela to Philadelphia in
    1850. Lawrence later married and they moved to Lee county,
    Illinois to farm. A Dempsey still lives on part of their farm

John Dempsey arrived with his
family from Tipperary in 1925. He rose through the political
ranks to be Governor of Connecticut from 1961 to 1970.

There were two famous Jack Dempseys in America who were world boxing

  • the first Jack Dempsey, known the Jack Dempsey the
    non pareil,
    came from Ireland but spent most of his boxing
    life in America. Sadly, he died young of TB.
  • the second,
    known as the Manassa Mauler, was born in Colorado from a family that
    had hailed originally from West Virginia. He lived on after
    retirement to run Jack Dempsey’s Restaurant in New

Australia. James Dempsey,
a United
Irishman, had been part of the Vinegar Hill rebellion in Wexford in
1798, resulting in his transportation to Australia. He was
granted his freedom in 1809 and his home became a spiritual and
communal center for the sizeable disenfranchised Irish Catholic
population of Sydney. He devoted his time, money, and effort in
later life to the building of the first Catholic chapel in Australia
for this community.

Among the later free settlers to Australia were:

  • Thomas O’Dempsey and his family on the Ballarat from Wexford in
    1828. They arrived in Melbourne.
  • Newly-weds James and Johanna Dempsey from Tipperary in
    1855. They came to Queensland and were one of the early settlers
    in Upper Freestone.


Dempsey Miscellany

The O’Dempseys of Clanmalier.  The following is the O’Dempsey line, from Dermod O’Dempsey’s father who died in 1162 through fourteen generations to the
O’Dempseys in the 17th century.

Name Date of Death
Conbrogha McHugh O’Dempsey   1162
Dermod McConbrogha O’Dempsey   1193
Hugh McDermod O’Dempsey
Fionn McMalachy O’Dempsey   1306
Dermod McFionn O’Dempsey   1308
Fionn McDermod O’Dempsey
Malachy McFionn O’Dempsey   1329
Dermod McMalachy O’Dempsey   1383
Maolmorra McDermod O’Dempsey   1407
Cahir McMaolmorra O’Dempsey   1445
Dermod McCahir O’Dempsey
Hugh McDermod O’Dempsey   1563
Dermod McHugh O’Dempsey   1565
Terence McDermod O’Dempsey   1639

Terence O’Dempsey was made Viscount Clanmalier by James I of England in 1631.  His grandson Lewis the second Viscount (who died in 1683) and great grandson Maximilian the third Viscount (who died in 1714) took up against the English and their lands were forfeited in 1691.

The O’Dempseys and Lea Castle.  Lea Castle lies on the outskirts of what is now the town of
Portarlington, on the banks of the Barrow river between Laois and
Offaly.  The castle was originally built by the Normans in 1260,
but it changed hands many times during its history.  It was taken
by the O’Dempseys in 1284 then surrendered in 1329, burned by the
O’Moores in 1346, captured by the O’Dempseys in 1422, and then taken by
the Earl of Ormond in 1452.

In 1642 the castle was occupied by the Confederate
Catholics, from which they were driven by Lord Lisle.  Eight years
later the castle was taken by Cromwell’s forces and dismantled.
The last person who took up his abode there was Charles O’Dempsey
(Cahir na gCapall), the last descendant of the once powerful Chiefs of

Dempseys of Lea Parish in Laios County.  Griffith’s Valuation of Ireland was undertaken over the
years 1848 to 1864.  It recorded the property owners in each
county.  Those in Queen’s county (now Laois county) showed sixty
three Dempseys.  Ten of them below were from Lea parish.

Name Parish Location
Andrew Dempsey Lea Kilbride
John Dempsey Lea Cooltedery
John Dempsey Lea Cooltedery (Bracklone St)
John Dempsey Lea Cooltedery (Main St)
John Dempsey Jr Lea Cooltedery (Main St)
Joseph Dempsey Lea Clonanny
Margaret Dempsey Lea Jamestown/Ballyteigeduff
Mary Dempsey Lea Cooltedery (Main St)
Michael Dempsey Lea Courtwood
Patrick Dempsey Lea Bolnagree

Reader Feedback – William Dempsey in Philadelphia in 1726.  In your Select Dempsey Surname Genealogy
you say that Barnet Dempsey may have been the earliest Dempsey arrival in
America during the 1780’s.

I have family written history that William
Dempsey (my 5th great grandfather), age 4, arrived in Philadelphia in
1726 in
the company of his uncle Mark.

His son,
John William Dempsey (my 4th great grandfather), fought under
Washington in the
American Revolution and may have been at Valley Forge.
John married Rachel Solomon (daughter of a
Jewish sea merchant) in Philadelphia after the conclusion of the war
and around
1790 made residence in Botetourt county, Virginia (now Mingo county,
Virginia).  His father William had lived at
Fincastle in Botetourt county.

Mark Dempsey (

Reader Feedback – Arthur O’Dempsay from Dublin to America.  I am looking for the parents of Arthur David O’Dempsay.  Born in Dublin in 1812, he trained as a MD in Ireland, (his father was probably an MD) and was reported to be a seminary student, age 15/16, at maybe Clongowes Woods.

He landed in Vermont in 1829 with wife Mary Ann Smith and baby Jane born at sea when the father was 17 years old.  I wonder if a pregnancy had caused his marriage to Mary and their trip to America as a couple.  He died in Washington, Illinois in 1895.  His tombstone and land records spelt name with an “a” (Dempsay).

Kathy Olin (

James Dempsey and the Early Catholic Church in Australia.  In the Catholic archives in Adelaide were found some anonymous scribbled notes which read as follows:

“James Dempsey, a stone mason, sent out
for the part he took in the rising of 1798 was a native of
Wexford.  A man of genuine piety, he often wept in his captivity,
for though his irreproachable character caused him to be allowed to
execute his trade and exempted him from being assigned, he felt his
deprivation of all religious aid as keenly as the Jews who ‘could not
sing the songs of the Lord in a strange land, who wept when they
remembered Zion.'”

He had been granted his pardon in 1809, the year the only Roman
Catholic priest in the New South Wales colony had been expelled.
An unconsumed Host was left behind by the priest and Dempsey kept this
at his house on Kent Street and used it as a rallying point for the
large Catholic population in Sydney.

When a priest finally arrived in 1820, Dempsey was still filled with
zeal and went about the construction of the first Catholic chapel in
Australia.  He started work on an undesirable piece of land on the
outskirts of the town.  He was to sink his whole fortune into its
building and it was to become his life’s work.  It pushed him into
bankruptcy and he travelled the world to raise funds for it.  The
chapel was finally completed some years before his death in 1838.

Jack Dempsey the Nonpareil.  Jack Dempsey was born in county Kildare in Ireland, but died of TB in
America in 1895.  He was just thirty three.

He was a middleweight boxer who became champion of the world.
Some people think that he was the greatest pound for pound boxer in
history.   He was a two-handed fighter who could box or
punch; his jab was quick and accurate; his right hand punch was stiff;
he was game and cool under pressure; and he could fight whatever style
was needed to win; in short, a crafty boxer-puncher who
was an excellent ring general.

M.J. McMahon wrote a poem to his memory.  Part of the poem read as

“Far out in the wilds of Oregon,
On a lonely mountainside,
Where Columbia’s mighty waters
Roll down to the ocean side;
Where the giant fir and cedar
Are imaged in the wave,
O’ergrown with firs and lichens,
I found Jack Dempsey’s grave.

O Fame, why sleeps thy favored son
In wilds, in woods, in weeds,
And shall he ever thus sleep on,
Interred his valiant deeds.
Tis strange New York should thus forget
Its ‘bravest of the brave’
And by the fields of Oregon,
Unmarked leave Dempsey’s grave.”

Jack Dempsey’s Restaurant.  Jack Dempsey’s was a New York restaurant located
on Broadway between 49th and 50th streets in Manhattan.  Owned by
world heavyweight boxing champion Jack Dempsey, it was considered by
many as an American institution.  It originally opened for
business in 1935 on Eighth Avenue and 50th Street, directly across from
the old Madison Square Garden.  Most nights would find Dempsey’s
famous proprietor on hand to greet guests, sign autographs, pose for
pictures and hold court.

A poster in the restaurant showed Dempsey crouching and bobbing his way
to a heavyweight victory over the giant Jess Willard to win the
championship of the world on July 14, 1919.

Jack Dempsey’s restaurant appeared in the 1972 movie The Godfather.  Michael
Corleone stood in front of Jack Dempsey’s while waiting to be picked up
by Virgil Sollozzo and Capt. McCluskey for their infamous dinner
meeting.   The restaurant closed two years later in 1974.


Select Dempsey Names

  • Dermot O’Dempsey, who died in 1193, was the first leader of the
    O’Dempsey clan. He led the Leinster resistance to the
    Anglo-Norman invasion under Strongbow.
  • James Dempsey built the first
    Roman Catholic chapel in Australia.
  • Jack Dempsey (born John Kelly) was an Irish-born boxer called the “nonpareil” because no one could beat him. He died in 1895 at the tender age of 33.
  • Jack Dempsey, known as the “Manassa Mauler,” was world heavyweight champion from 1919 to 1926.

Select Dempsey Numbers

  • 8,000 in the UK (most numerous
    in London)
  • 10,000 in America (most numerous
    in New York)
  • 16,000 elsewhere (most numerous in Ireland).


Select Dempsey and Like Surnames 

The Irish clan or sept names come through the mists of time until they were found in Irish records such as The Annals of the Four Masters.  The names were Gaelic and this Gaelic order was preserved until it was battered down by the English in the 1600’s.

Some made peace with the English.  “Wild geese” fled to fight abroad.  But most stayed and suffered, losing land and even the use of their language.  Irish names became anglicized, although sometimes in a mishmash of spellings.  Mass emigration happened after the potato famine of the 1840’s.

Some surnames – such as Kelly, Murphy and O’Connor – span all parts of Ireland.  But most will have a territorial focus in one of the four Irish provinces – Leinster, Munster, Ulster, and Connacht.

Leinster in SE Ireland covers the counties of Carlow, Dublin, Kilkenny, Offaly, Laois, Longford, Louth, Meath, West Meath, Wexford, and Wicklow.  Here are some of the Leinster surnames that you can check out.




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