Biography of Lionel Plantagenet 1st Duke of Clarence 1338-1368
Paternal Family Tree: Anjou aka Plantagenet
Maternal Family Tree: Elizabeth Cuman
York Minster
Antwerp
Eltham Palace, Kent
Dublin
Clare Priory, Suffolk
Kilkenny, Ireland
Alba
On 25 Jan 1327 [his grandfather] King Edward II of England (age 42) abdicated II King England. His son [his father] King Edward III of England (age 14) succeeded III King England.
On 24 Jan 1328 [his father] King Edward III of England (age 15) and [his mother] Philippa of Hainault (age 13) were married at York Minster [Map]. She by marriage Queen Consort England. She was crowned the same day. She the daughter of [his grandfather] William Hainault I Count Hainault III Count Avesnes III Count Holland II Count Zeeland (age 42) and Joan Valois Countess Zeeland Holland Avesnes and Hainault (age 34). He the son of [his grandfather] King Edward II of England and [his grandmother] Isabella of France Queen Consort England (age 33). They were second cousins. She a great x 5 granddaughter of King Henry "Curtmantle" II of England. 
The marriage was the quid pro quo for her father William Hainault I Count Hainault III Count Avesnes III Count Holland II Count Zeeland (age 42) having supported his mother Isabella of France Queen Consort England (age 33) and Roger Mortimer 1st Earl March (age 40) returning to England to usurp the throne of Edward's father King Edward II of England.
Annals of Ulster 1333. 06 Jun 1333. William Burke, Earl of Ulster (age 20)2, was killed by the English of Ulster. The Englishmen who committed this deed were put to death, in divers ways, by the people of the King of England; some were hanged, others killed, and others torn asunder2, in revenge of his death.
Note 1. Earl of Ulster. There is a much more circumstantial account of the death of this Earl of Ulster given by Pembridge and Grace under this year. Lodge gives the following particulars of it: "He was murdered on Sunday, June 6, 1333, by Robert Fitz-Richard Mandeville (who gave him his first wound), and others his servants, near to the Fords, in going towards Carrickfergus, in the 21 st year of his age, at the instigation, as was said, of Gyle de Burgh, wife of Sir Richard Mandeville, in revenge for his having imprisoned her brother Walter and others."
This young earl left an only child, [his future wife] Elizabeth, who was married in the year 1352 to Lionel, third son of King Edward III., and this prince was then created, in her right, Earl of Ulster and Lord of Connaught, and these titles were enjoyed through marriage or descent by different princes of the royal blood, until at length, in the person of Edward IV, they became the special inheritance and revenue of the crown of England. Immediately on the Earl's death the chiefs of the junior branches of the family of Burke or De Burgo, then seated in Connaught, fearing the transfer of his possessions into strange hands by the marriage of the heiress, seized upon his estates in Connaught. The two most powerful of these were Sir William or Ulick, the ancestor of the Earls of Clanrickard, and Sir Edmund Albanagh the progenitor of the Viscounts of Mayo. These having confederated together and declared themselves independent, renounced the English dress and language, and adopted Irish names, Sir William taking the name of Mac William Oughter, or the Upper, and Sir Edmund that of Mac William Eighter, or the Lower. Under these names these two powerful chieftains tyranized over the entire province of Counaught, and though Lionel Duke of Clai'ence, in right of his wife, laid claim to their usurped possessions, the government apears to have been too weak to assert, the authority of the English laws, so that the territories of the Burkes were allowed to descend in course of tanistry and gavelkind. See Hardiman's History of Galway, pp. 56, 57.
Note 2. Torn asunder, i.e. torn limb from limb. Mageoghegan renders it "hanged, drawn, and quartered."
On 29 Nov 1338 Lionel Plantagenet 1st Duke of Clarence was born to King Edward III of England (age 26) and Philippa of Hainault Queen Consort England (age 24) at Antwerp [Map]. Coefficient of inbreeding 3.00%. 
In 1342 [his brother] John of Gaunt 1st Duke Lancaster (age 1) was created 1st Earl Richmond. It isn't clear whether his older brothers [his brother] Edward "Black Prince" (age 11) and Lionel Plantagenet 1st Duke of Clarence (age 3) had been created Earls before this time.
In 1352 Lionel Plantagenet 1st Duke of Clarence (age 13) and Elizabeth Burgh Duchess of Clarence (age 19) were married. He by marriage Earl Ulster. She was the sole heir of her father and brought the de Burgh inheritance of the lands of Ulster to the marriage. As a consequence of their earlier betrothal he had been called Earl Ulster since 1347. She the daughter of William Donn Burgh 3rd Earl Ulster and Maud Plantagenet Countess Ulster (age 42). He the son of King Edward III of England (age 39) and Philippa of Hainault Queen Consort England (age 37). They were half second cousin once removed. She a great x 2 granddaughter of King Henry III of England. 
On 16 Aug 1355 [his daughter] Philippa Plantagenet Countess March 5th Countess Ulster was born to Lionel Plantagenet 1st Duke of Clarence (age 16) and [his wife] Elizabeth Burgh Duchess of Clarence (age 23) at Eltham Palace, Kent [Map]. At the time of her birth she was Heir to the Throne of England since her uncle [his brother] Edward "Black Prince" (age 25) was yet to be married. She a granddaughter of King Edward III of England. Coefficient of inbreeding 2.22%.
Archaeologia Volume 35 1853 XXXIII. On the 1st of March [1358], the Earl of Ulster, Lionel (age 19), afterwards Duke of Clarence, son of Edward III., takes supper with the [his grandmother] Queen (age 63). It will be remembered that Lionel's daughter, Philippa (age 2), subsequently brought a claim to the English crown into the family of the Mortimers, by her marriage with Edmund Earl of March (age 6).
On 08 Oct 1360 [his future brother-in-law] Gian Galeazzo Visconti 1st Duke Milan (age 8) and Isabelle Valois (age 12) were married. She the daughter of King John "The Good" II of France (age 41) and Bonne Luxemburg Queen Consort France. She a great x 5 granddaughter of King Henry "Curtmantle" II of England. 
In 1361 [his father] King Edward III of England (age 48) created three of his sons as Garter Knights ...
35th Lionel Plantagenet 1st Duke of Clarence (age 22).
36th [his brother] John of Gaunt 1st Duke Lancaster (age 20).
37th [his brother] Edmund of Langley 1st Duke York (age 19).
38th Edward Despencer 1st Baron Despencer, Baron Burghesh (age 25).
On 13 Nov 1362, his fiftieth birthday, [his father] King Edward III of England (age 50) created two sons as Dukes ...
Lionel Plantagenet 1st Duke of Clarence (age 23) was created 1st Duke Clarence. [his wife] Elizabeth Burgh Duchess of Clarence (age 30) by marriage Duchess Clarence.
[his brother] John of Gaunt 1st Duke Lancaster (age 22) was created 1st Duke Lancaster. Blanche Plantagenet Duchess Lancaster (age 17) by marriage Duchess Lancaster.
On 10 Dec 1363 [his wife] Elizabeth Burgh Duchess of Clarence (age 31) died at Dublin [Map]. She was buried at Clare Priory, Suffolk [Map].
In 1366 Lionel Plantagenet 1st Duke of Clarence (age 27) held a Parliament at Kilkenny, Ireland [Map]. The Parliament enacted thirty-five statutes known as the Statutes of Kilkenny which began:
... now many English of the said land, forsaking the English language, manners, mode of riding, laws and usages, live and govern themselves according to the manners, fashion, and language of the Irish enemies; and also have made divers marriages and alliances between themselves and the Irish enemies aforesaid; whereby the said land, and the liege people thereof, the English language, the allegiance due to our lord the king, and the English laws there, are put in subjection and decayed...
In 1367 Lionel Plantagenet 1st Duke of Clarence (age 28) returned to England.
In Jun 1368 Lionel Plantagenet 1st Duke of Clarence (age 29) and Violante Visconti (age 14) were married in the Church of Santa Maria Maggiore, Milan. The wedding festivities were lavish and ostentatious. The banquet, held outside, included 30 courses of meat and fish presented fully gilded. Between the courses the guests were given gifts such as suits of armor, bolts of cloth, war horses, arms, and hunting dogs. Among the guests were Geoffrey Chaucer (age 25), Petrarch, Jean Froissart and John Hawkwood. He the son of King Edward III of England (age 55) and Philippa of Hainault Queen Consort England (age 53).
On 07 Oct 1368 Lionel Plantagenet 1st Duke of Clarence (age 29) died from poisoning at Alba [Map]. Duke Clarence extinct. He was buried at the St Pietro Ciel d'Oro Church, Pavia.
There was strong speculation he had been poisoned by his [his wife] wife's (age 14) [his father-in-law] father (age 48).
Around 1377 Lionel Plantagenet 1st Duke of Clarence was reburied at Clare Priory, Suffolk [Map]. [his daughter] Philippa Plantagenet Countess March 5th Countess Ulster (age 21) succeeded 5th Countess Ulster.
In Nov 1386 [his former wife] Violante Visconti (age 32) died in Pavia.
Kings Wessex: Great x 9 Grand Son of King Edmund "Ironside" I of England
Kings England: Son of King Edward III of England
Kings Scotland: Great x 7 Grand Son of Malcolm III King Scotland
Kings Franks: Great x 5 Grand Son of Louis VII King Franks
Kings France: Great Grand Son of Philip "The Fair" IV King France
King Richard III of England x 1
Queen Elizabeth II of the United Kingdom x 34
Queen Consort Camilla Shand x 15
Great x 4 Grandfather: King Henry "Curtmantle" II of England Grand Son of King Henry I "Beauclerc" England
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Great x 4 Grandmother: Gersenda II Sabran Countess Provence
Great x 2 Grandmother: Eleanor of Provence Queen Consort England
Great x 4 Grandfather: Thomas Savoy I Count Savoy
Great x 3 Grandmother: Beatrice Savoy Countess Provence
Great x 4 Grandmother: Margaret Geneva Countess Savoy
GrandFather: King Edward II of England Son of King Edward "Longshanks" I of England
Great x 4 Grandfather: Ferdinand II King Leon
Great x 3 Grandfather: Alfonso IX King Leon
Great x 4 Grandmother: Urraca Burgundy Queen Consort Leon
Great x 2 Grandfather: Ferdinand III King Castile III King Leon Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Alfonso VIII King Castile
Great x 3 Grandmother: Berengaria Ivrea I Queen Castile Grand Daughter of King Henry "Curtmantle" II of England
Great x 4 Grandmother: Eleanor Plantagenet Queen Consort Castile Daughter of King Henry "Curtmantle" II of England
Great x 1 Grandmother: Eleanor of Castile Queen Consort England 2 x Great Grand Daughter of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Alberic Dammartin
Great x 3 Grandfather: Simon Dammartin
Great x 4 Grandmother: Mathilde Clermont
Great x 2 Grandmother: Joan Dammartin Queen Consort Castile and Leon
Great x 4 Grandfather: William Montgomery IV Count Ponthieu
Great x 3 Grandmother: Marie Montgomery Countess Ponthieu
Great x 4 Grandmother: Alys Capet Countess Ponthieu
Father: King Edward III of England Son of King Edward II of England
Great x 4 Grandfather: Louis "Lion" VIII King France 3 x Great Grand Son of King William "Conqueror" I of England
Great x 3 Grandfather: King Louis IX of France Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandmother: Blanche Ivrea Queen Consort France Grand Daughter of King Henry "Curtmantle" II of England
Great x 2 Grandfather: Philip "Bold" III King France 2 x Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Raymond Berenguer Provence IV Count Provence
Great x 3 Grandmother: Margaret Provence Queen Consort France
Great x 4 Grandmother: Beatrice Savoy Countess Provence
Great x 1 Grandfather: Philip "The Fair" IV King France 3 x Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Peter II King Aragon
Great x 3 Grandfather: James I King Aragon
Great x 4 Grandmother: Marie Montpellier Queen Consort Aragon
Great x 2 Grandmother: Isabella Barcelona Queen Consort France
Great x 4 Grandfather: King Andrew II of Hungary
Great x 3 Grandmother: Violant Árpád Queen Consort Aragon
GrandMother: Isabella of France Queen Consort England 4 x Great Grand Daughter of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Theobald Blois III Count Champagne
2 x Great Grand Son of King William "Conqueror" I of England
Great x 3 Grandfather: Theobald IV King Navarre 3 x Great Grand Son of King William "Conqueror" I of England
Great x 4 Grandmother: Blanche Ramirez
Great x 2 Grandfather: Henry I King Navarre 4 x Great Grand Son of King William "Conqueror" I of England
Great x 4 Grandfather: Archambaud "Great" Dampierre
Great x 3 Grandmother: Margaret Bourbon Queen Consort Navarre
Great x 4 Grandmother: Alix Forez
Great x 1 Grandmother: Joan Blois I Queen Navarre 3 x Great Grand Daughter of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Louis "Lion" VIII King France 3 x Great Grand Son of King William "Conqueror" I of England
Great x 3 Grandfather: Robert Capet Count of Artois Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandmother: Blanche Ivrea Queen Consort France Grand Daughter of King Henry "Curtmantle" II of England
Great x 2 Grandmother: Blanche Capet Queen Navarre 2 x Great Grand Daughter of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Henry Reginar II Duke Brabant 3 x Great Grand Son of King William "Conqueror" I of England
Great x 3 Grandmother: Matilda Reginar Countess Saint Pol 4 x Great Grand Daughter of King William "Conqueror" I of England
Great x 4 Grandmother: Marie Swabia Duchess Brabant
Lionel Plantagenet 1st Duke of Clarence Son of King Edward III of England
Great x 4 Grandfather: James Avesnes
Great x 3 Grandfather: Bouchard Avesnes
Great x 4 Grandmother: Adela Guise
Great x 2 Grandfather: John Hainault I Count Hainault 4 x Great Grand Son of King William "Conqueror" I of England
Great x 4 Grandfather: Baldwin IX Count Flanders VI Count Hainault
Great x 3 Grandmother: Margaret II Countess Flanders 3 x Great Grand Daughter of King William "Conqueror" I of England
Great x 4 Grandmother: Marie Blois Countess Flanders 2 x Great Grand Daughter of King William "Conqueror" I of England
Great x 1 Grandfather: John Hainault II Count Hainault II Count Holland 5 x Great Grand Son of King William "Conqueror" I of England
Great x 4 Grandfather: William Gerulfing I Count Holland
Great x 3 Grandfather: Floris Gerulfing IV Count Holland
Great x 4 Grandmother: Adelaide Guelders Countess Holland
Great x 2 Grandmother: Adelaide Gerulfing Countess Hainault 4 x Great Grand Daughter of King William "Conqueror" I of England
Great x 4 Grandfather: Henry Reginar VIII Duke Lower Lorraine I Duke Brabant
Great x 3 Grandmother: Mathilde Reginar Countess Holland and Palatine 3 x Great Grand Daughter of King William "Conqueror" I of England
Great x 4 Grandmother: Maud Metz 2 x Great Grand Daughter of King William "Conqueror" I of England
GrandFather: William Hainault I Count Hainault III Count Avesnes III Count Holland II Count Zeeland 6 x Great Grand Son of King William "Conqueror" I of England
Great x 4 Grandfather: Henry Luxemburg III Duke Limburg
Great x 3 Grandfather: Waleran Luxemburg III Duke Limburg
Great x 4 Grandmother: Sophia Saarbrücken Duchess Limburg
Great x 2 Grandfather: Henry "Great" Luxemburg V Count Luxemburg III Count Namur
Great x 4 Grandfather: Henry "Blind" Namur IV Count Luxemburg I Count Namur
Great x 3 Grandmother: Erminsende Namur Countess of Bar
Great x 4 Grandmother: Agnes Guelders Countess Namur and Luxemburg
Great x 1 Grandmother: Philippa Luxemburg Countess Hainault and Holland 5 x Great Grand Daughter of King William "Conqueror" I of England
Great x 4 Grandfather: Theobald of Bar I Count of Bar 2 x Great Grand Son of King William "Conqueror" I of England
Great x 3 Grandfather: Henry of Bar II Count of Bar 3 x Great Grand Son of King William "Conqueror" I of England
Great x 4 Grandmother: Erminsende of Bar Sur Seine Countess Bar
Great x 2 Grandmother: Margaret of Bar Countess Luxemburg and Namur 4 x Great Grand Daughter of King William "Conqueror" I of England
Great x 4 Grandfather: Robert Capet II Count Dreux
Great x 3 Grandmother: Philippa Capet Countess of Bar
Great x 4 Grandmother: Yolande Coucy Countess Dreux
Mother: Philippa of Hainault Queen Consort England 5 x Great Grand Daughter of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Louis "Lion" VIII King France 3 x Great Grand Son of King William "Conqueror" I of England
Great x 3 Grandfather: King Louis IX of France Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandmother: Blanche Ivrea Queen Consort France Grand Daughter of King Henry "Curtmantle" II of England
Great x 2 Grandfather: Philip "Bold" III King France 2 x Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Raymond Berenguer Provence IV Count Provence
Great x 3 Grandmother: Margaret Provence Queen Consort France
Great x 4 Grandmother: Beatrice Savoy Countess Provence
Great x 1 Grandfather: Charles Valois I Count Valois 3 x Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Peter II King Aragon
Great x 3 Grandfather: James I King Aragon
Great x 4 Grandmother: Marie Montpellier Queen Consort Aragon
Great x 2 Grandmother: Isabella Barcelona Queen Consort France
Great x 4 Grandfather: King Andrew II of Hungary
Great x 3 Grandmother: Violant Árpád Queen Consort Aragon
GrandMother: Joan Valois Countess Zeeland Holland Avesnes and Hainault 4 x Great Grand Daughter of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Louis "Lion" VIII King France 3 x Great Grand Son of King William "Conqueror" I of England
Great x 3 Grandfather: King Charles Capet of Sicily Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandmother: Blanche Ivrea Queen Consort France Grand Daughter of King Henry "Curtmantle" II of England
Great x 2 Grandfather: Charles II King Naples 2 x Great Grand Son of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Raymond Berenguer Provence IV Count Provence
Great x 3 Grandmother: Beatrice Provence Queen Consort Sicily
Great x 4 Grandmother: Beatrice Savoy Countess Provence
Great x 1 Grandmother: Margaret Capet Countess Valois 3 x Great Grand Daughter of King Henry "Curtmantle" II of England
Great x 4 Grandfather: Béla IV King of Hungary
Great x 3 Grandfather: Stephen V of Hungary
Great x 2 Grandmother: Mary of Hungary Queen Consort Naples
Great x 3 Grandmother: Elizabeth Cuman