'Cusack01'Index links to: Lead / Letter DRAFT
Families covered: Cusack of Cussington, Cusack of Gerardstown, Cusack of Killeen, Cusack of Lismullen
This family is still being researched. It has NOT yet been launched formally into the Database but is shown here as DRAFT in the hope that one or more visitors to the site will contribute information that will enable us to develop this Family List to an acceptable standard.
First displayed: 01.03.12Last updated: 01.03.12
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Wikipedia ("Cusack") records a report that there was a Sn. de Cussac who accompanied the orginal Norman invasion. However, Wikipedia and various other web sites suggest that the ancestor of this family was the following Geoffrey who came from Cussac, in Guienne (Aquitaine), in about 1172. He is reported to have joined the invasion of Ireland and built Killeen Castle.
Geoffrey de Cusac, later of Killeen Castle (a 1172, 1210)
Some web sites suggest that it was this Geoffrey who married the Petit heiress but BLG1886 jumps from the above Geoffrey to the following one and identifies him as her husband. From the dates we presume that there was an intevening generation but such is not certain.
1. ?? de Cusac presumed intermediary generation
  A. Geoffrey de Cusack, lord of Killeen (a 1295)
  BLG1886 identifies Geofrey's wife as the dau/heir of Adam Petit. Various web sites name her as ...
  m. Marilda le Petit (dau/heir of Adam le Petit of Dunboyne)
  i. Adam de Cusack, lord of Killeen
Various web sites report that Killeen passed out of the family through the undermentioned marriage of the heiress Joan.
  a. ?? de Cusac
  Uncertain on number of intervening generations. TCP (Killeen) provides the following.
  (1) Sir Walter de Cusake
  m. ?? (granddau/heir of Richard Tuite of Killeen Manor)
  (A) Sir Luke de Cusake or Cusack, lord of Killeen
  m. Matilda Fleming (dau of the Baron of Slane) mentioned in various web sites
  i) Joan de Cusack
  m. (before 10.1399) Christopher Plunkett of Rathregan & Killeen
  ii. Sir Andrew Cusack of Gerardstown (d 1295)
  BLG1886 identifies Andrew as "ancestor of the Cusacks, Lords of Culmolyn, Dangan, and Dunsaney"
  m. Maud Pilate (dau/coheir of William Pilate of Puilatestown, sister of Isabella, lady Howth)
  a. Sir John Cusack, 2nd of Gerardstown
  (1) ?? Cusack
  (A) ?? Cusack
  (i) ?? Cusack
  (a) ?? Cusack
  Uncertain on number of intervening generations.
  ((1)) ?? Cusack
  ((A)) ?? Cusack
((i)) ?? Cusack possibly Sir Nicholas, father of Catherine
  ((a)) ?? Cusack possibly Thomas, father of Elizabeth
  Commoners (vol 1, p544) shows that a Thomas of Gerardstown was father of Elizabeth by Anne, dau of Nicholas (sb Robert?) St. Lawrence, Lord Howth, by Joan, dau of Edmond, Duke of Somerset. This will be investigated further in due course.
  (((1))) ?? Cusack
  (((A))) Robert Cusack, 14th of Gerardstown (d 28.04.1632)
  m1. Margaret Porter of Kingstown
  m2. Margaret (dau of Oliver, Lord Louth)
  (((2))) Elizabeth Cusack possbly of this generation
  m. (1563) Patrick Delafield
  ((b)) Catherine Cusack possbly of this generation
  m. William Dowdall of Mounttown
  b.+ other issue (a 1299) - Sir Simon, Sir Walter
  iii. William Cusack (youngest son) identified by BLG1886 as "ancestor of the line of Cussington"
  a. ?? Cusack
  Uncertain on number of intervening generations.
  (1) ?? Cusack
  The following connection to John of Cussington, father of Sir Thomas, comes from a RootsWeb site (see here). It is our presumption that the following Barnaby was descended from the above-mentioned William.
  (A) Sir Barnaby Cusack in Gerardstown (b 1359)
  m. Eliza Crompe
  (i) David Cusack (b 1390, d 1438)
(a) Sir Walter Cusack (b 1415, d 1487)
  m1. (1435) Jean Elizabeth Plunkett (dau of John Plunkett of Killeen by Elizabeth Hollywood)
  ((1)) John Cusack of Cussington, co. Meath
  The following is supported by BP1934 ('Wellington').
  m. (1474) Alison Wellesley (dau of Sir William Wellesley of Dangan)
  ((A)) Sir Thomas Cusack of Cussington 'of Lismullen', Chancellor of Ireland (b 1490, d 1571)
  BP1934 ('Wellington') only mentions Sir Thomas's marriage to Maud D'Arcy and confirms Catherine (and, by cross-reference, Genet) as their children. Most of the rest of the following comes from Wikipedia ("Thomas Cusack (Irish judge)").
m1. (div in 1537) Joan Hussey
  ((i))+ "at least three children"
  m2. Maud D'Arcy (dau of George D'Arcy of Platten)
((iv)) Robert Cusack (d 1570, Baron of the Exchequer) possibly the Robert of Cossington who was father of ...
  ((a)) Margaret Cusack
  m. John Plunkett
  ((b)) Anne Cusack
  m. Richard Luttrell of Tankardstown (d 10.1633)
  ((v)) Edward Cusack possibly the Edward of Lismullen who married ...
m. Lucinda Talbot (sister of Richard Talbot, Duke of Tyrconnell)
  ((a)) Cecilia Cusack
  m. Thomas Cusack of Staffordstown
  ((vi)) John Cusack
  ((vii)) Catherine Cusack (d 19.01.1597)
  m1. Sir Henry Colley of Castle Carbery & Edenderry (d 1584)
m2. William Eustace
  ((viii)) Genet Cusack
  m. George Wesley of Dangan & Mornington (d 13.05.1603)
  ((ix)) Mary Cusack
  m. Theobald Butler, 1st Lord Caher (d 28.04.1596)
  ((x)) Alice Cusack
  m. Sir Christopher Bellew
This connection looks questionable unless either Alice was years older than her husband or the date given for the marriage of Sir Christopher's parents was wrongly given (as 1599).
  ((xi)) Margaret Cusack
m. Murrough O'Brien, Baron Inchiquin
  ((xii)) Alison Cusack
  m. Thomas Aylmer
  ((xiii)) Anne Cusack probably of this generation
  m. John Dowdall of Glasspistol
  ((xiv))+ other issue
  m3. Jenet Sarsfield
  ((2))+ other issue - Nicholas, Thomas
  m2. (1444) Elizabeth Mareward
  (b)+ other issue - Thomas, Christopher of Taragh
  iv.+ other issue - Nicholas (d 1299, Bishop of Kildare), Geoffry (d 1300, Bishop of Meath)

Main source(s): BLG1886 ('Cusack of Gerardstown') with input/support as reported above
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