Recently it was the anniversary of John of Gaunt's birth on 6 March 1340. John, the fourth but third eldest surviving son* of Edward III and Philippa of Hainault, was born in the abbey of St Bavo in Ghent, in modern-day Belgium. Ghent was called 'Gaunt' in England in the fourteenth century and afterwards, and therefore John of Ghent has always been known as John of Gaunt.
* His older brothers were Edward of Woodstock (b. June 1330), William of Hatfield (b. and d. early 1337) and Lionel of Antwerp (b. November 1338). His older sisters were Isabella of Woodstock (b. June 1332) and Joan of Woodstock (b. c. January 1334).
Below, from the parliament rolls in 1383: la ville de Gaunt, 'the town of Ghent'.
A lot of people, I noticed in the flurry of posts and articles about him recently, misunderstand John of Gaunt's possession of the Lancastrian lands, so here's some information about it. John married his first wife Blanche of Lancaster (c. 25 March 1342 - 12 September 1368) in Reading on 19 May 1359. Blanche was the younger daughter and co-heir, with her sister Maud (b. c. 4 April 1340), duchess of Lower Bavaria and countess of Hainault and Holland, of her father Henry of Grosmont (b. c. 1310/12), first duke of Lancaster and earl of Lincoln, Leicester and Derby. After Henry's death on 23 March 1361, his lands in thirty-four English counties and in Wales were divided equally between his two daughters. Although there's no record of her death, Maud and Blanche's mother Isabella Beaumont must have died before Henry, because otherwise she would have been assigned dower, and, as a third of the Lancastrian lands, it would have been considerable and we would have a record of it.
Blanche and her husband John of Gaunt received the Lancastrian lands in the north of England and some of the lands in the Midlands, including the Yorkshire castles of Pontefract and Pickering, the Lincolnshire castle of Bolingbroke, the Staffordshire castle of Tutbury, and Dunstanburgh Castle in Northumberland, built in the 1310s and early 1320s by Blanche's great-uncle Thomas of Lancaster. Maud, who in 1352 married Wilhelm von Wittelsbach, a son of the late Holy Roman Emperor Ludwig or Louis of Bavaria, and lived on the continent, received the lands in Wales, the south of England and some in the Midlands, including five castles in South Wales and the castles of Newcastle-under-Lyme and Leicester. In an inquisition of 1362, the Savoy Palace in London, re-built on a magnificently opulent scale by Duke Henry after he inherited it from his father in 1345 but described rather hilariously in the inquisition as 'certain tenements called the Saveye', was said to have been held jointly by Maud and her brother-in-law John of Gaunt in the year since Henry's death. Maud also received the French lordship of Beaufort, once held by her great-uncle John of Lancaster (d. 1317). As well as the Lancastrian estates held by their father Duke Henry, grandfather Earl Henry, great-uncles Thomas and John of Lancaster and great-grandfather Edmund of Lancaster, the two sisters also inherited the lands of the de Lacy family which formerly belonged to their father's aunt-in-law Alice de Lacy, countess of Lincoln (1281-1348), and the lands and lordships in England and Wales once held by their paternal grandmother Maud Chaworth (1282-1322). See family trees below.
Maud of Lancaster outlived her father by only a year, and died at the age of 22 on 9 or 10 April 1362. According to a continental chronicle, she was buried in the Benedictine abbey of Rijnsburg near Leiden, a city now in the South Holland province of the Netherlands. She and her husband Wilhelm (b. 1330), duke of Lower Bavaria and count of Hainault and Holland, had had a daughter in 1356 when Maud was 16, but the little girl died in infancy. Wilhelm of Bavaria, incidentally, was John of Gaunt's first cousin: Wilhelm's mother Margareta of Hainault (1310-56), Holy Roman Empress, was the eldest sister of John's mother Queen Philippa. The unfortunate Wilhelm became insane around 1357/58 and had to be incarcerated for his own safety, and Edward III sometimes addressed letters to Wilhelm’s younger brother and heir Albrecht as the man in charge of looking after him. For thirty years until his death in 1388, poor Wilhelm was held in a tower of Le Quesnoy Castle (Le Quesnoy is a town now in the Nord department of France near the Belgian border), and Maud of Lancaster - the situation was so awful and tragic for both of them - lost her husband in all but name when she was still only a teenager. She remained near her husband on the continent, however, and the fact that she was buried in Rijnsburg surely indicates that she didn't die in England. Poor Maud, despite the unimaginable wealth she inherited, her life was short and sad. Incidentally, I'm not even going to bother to deal with the rumour that John of Gaunt had his sister-in-law poisoned; it's too silly to waste my time on. In Maud's inquisition post mortem of April/May 1362, jurors announced that "[t]he lady Blanche of Lancaster her sister, aged 20 years and married to Sir John, earl of Richmond, is her heir." Blanche and John now held all the Lancastrian inheritance, and John was made the second duke of Lancaster in November 1362 when his father Edward III celebrated his fiftieth birthday by raising his three middle sons to higher titles.
The Lancastrian heir after Blanche was her and John of Gaunt's only surviving son Henry of Lancaster (or Henry of Bolingbroke, as Shakespeare calls him), later King Henry IV, born in Bolingbroke, Lincolnshire in April 1367. A medieval custom called the 'courtesy of England' allowed a man who married an heiress to keep her entire inheritance after her death, for the rest of his own life, as long as they had at least one child together who lived long enough to take a breath. (Women, by contrast, held only a third of their late husband's lands as dower, but this right applied in all circumstances and not only when a couple had children.) John of Gaunt was the father of Blanche of Lancaster's children, and therefore, had the right to hold all her lands after her death at the age of 26 in September 1368 until his own death thirty years later in February 1399. John did not and could not inherit the Lancastrian estate, because he was not the child of Henry of Grosmont. His wife and his son, not John himself, were the Lancastrian heirs.
On John's death in February 1399, his and Blanche's son Henry of Lancaster should have come into his inheritance from his long-dead mother, though in fact did not because his cousin Richard II had exiled him from England some months earlier. As well as the extensive Lancastrian lands, Henry held another rich estate. His wife Mary de Bohun (c. 1370-94) was the co-heir, with her older sister Eleanor (c. 1366-99), of their father Humphrey de Bohun (1342-73), earl of Hereford, Essex and Northampton. Like his father, Henry of Lancaster benefited from the 'courtesy of England', because he was the father of Mary's children. After her death in 1394, therefore, he was entitled to hold Mary's one-third of the de Bohun inheritance for the rest of his life; another third was held by his sister-in-law Eleanor and her husband Thomas of Woodstock, duke of Gloucester, John of Gaunt's youngest brother; and the remaining third was held by Eleanor and Mary's long-lived mother Joan Fitzalan, Humphrey de Bohun's widow, as dower. When Joan died in 1419, her dower lands were shared out between two of her grandchildren: Henry V, Mary de Bohun's eldest son and heir, and Anne, countess of Stafford, Eleanor de Bohun's only living secular child and heir. Another beneficiary of the 'courtesy of England' was John of Gaunt's older brother Lionel of Antwerp (1338-68), whose first wife Elizabeth de Burgh (1332-63) inherited the earldom of Ulster and a third of the earldom of Gloucester, and another was Gaunt's nephew-in-law Edmund Mortimer, earl of March (1352-81), who outlived his wife Philippa of Clarence (1355- c. 1379), Lionel and Elizabeth's daughter and heir.
There were several factors which neither John of Gaunt nor anyone else could have anticipated which allowed him to hold *all* the Lancaster lands for decades: the early death of his sister-in-law Maud at age 22; the death in infancy of Maud's only daughter some years earlier; and the insanity of Maud's husband Wilhelm von Wittelsbach, duke of Lower Bavaria and count of Hainault and Holland, and the fact that Wilhelm had to be incarcerated in c. 1358 for the remaining thirty years of his life. Otherwise, assuming that Maud and Wilhelm's daughter wasn't stillborn, Wilhelm would have been entitled, as Maud's widower and the father of her child, to hold half of the Lancastrian estate until his death in 1388. He was, however, unable to travel to England and claim his late wife's lands. Obviously, Wilhelm wasn't English, but there was a process called denization that allowed foreigners to hold, though not to inherit, lands in England. Two of the many people granted denization were Lucia Visconti, widow of Edmund Holland, earl of Kent (d. 1408), and Beatriz of Portugal, widow of Thomas Fitzalan, earl of Arundel (d. 1415), so that they could hold their dower lands from their late husbands. I'm not entirely certain about the law regarding the holding of lands in the case of insanity, though there are numerous examples in the chancery rolls of guardians being appointed to look after lands held by those deemed to suffer from 'idiocy' (not my word). Even if Wilhelm had been able to leave his tower at le Quesnoy and travel to England, given his condition it seems doubtful that he would have been able to hold Maud's lands. Certainly, there's no record of him ever receiving any income from them. It may be that his and Maud's daughter was stillborn in 1356, and if that was the case, the little girl's birth wouldn't have 'counted' for the purposes of the courtesy of England.
And finally, let's examine what would have happened if John of Gaunt and Blanche of Lancaster had had no children. This, admittedly, is a big what-if, as it wipes out Blanche's son Henry IV, his son Henry V, her daughter Philippa, queen of Portugal, and Philippa's Portuguese children the Illustrious Generation, among numerous others. Primogeniture, whereby the eldest son inherited everything, did not apply to female heirs, who inherited equal parts of an estate, and being the eldest daughter conferred no advantage. This was why Maud and Blanche of Lancaster were joint and equal heirs to their father Henry of Grosmont in 1361. They had an older sister, Isabella of Lancaster, who is mentioned on record in 1338/39 but who must have died young; if she had lived, Isabella would have been another joint and equal heir to the Lancastrian fortune.
If Henry of Grosmont, first duke of Lancaster, had had younger brothers, the eldest of the brothers if alive, or his children if dead, would have been heir to a putative childless Blanche. Duke Henry, however, had no brothers, but six sisters: in birth order, they were Blanche (d. 1380), Isabella (d. 1348/9), Maud (d. 1377), Joan (d. 1349), Eleanor (d. 1372) and Mary (d. 1362). Blanche the eldest was married to Thomas, Lord Wake for thirty-three years but had no children, and Isabella the second was veiled as a nun of Amesbury Priory and became its prioress. Maud's heirs were her daughters, Elizabeth de Burgh, duchess of Clarence and countess of Ulster (1332-63), and Maud Ufford, countess of Oxford (1345/6-1413); Joan's heir was her only son, John, Lord Mowbray (1340-68); Eleanor's heir was her eldest son, Henry, Lord Beaumont (1339-69); and Mary's heir was her eldest son, Henry, Lord Percy, later the first earl of Northumberland (1341-1408).
If, for whatever reason, Blanche of Lancaster had never had children, her surviving aunts and the children of her other aunts would have been co-heirs to the vast Lancastrian estate on her death, in line with the law that female heirs, or their children if they were dead, received equal portions of an inheritance. If John of Gaunt and Blanche had had no child who lived long enough to take a breath, John would have had no claim to any part of his wife's lands after her death. 'Old John of Gaunt, time-honoured Lancaster' would not have been Lancaster. And finally, assuming that John and Blanche did have their children but that Wilhelm von Wittelsbach and Maud of Lancaster's daughter lived for a while after her birth in 1356 and Wilhelm didn't become incapacitated in c. 1358, John would have had to share the Lancastrian estate with his German cousin and brother-in-law until Wilhelm's death in 1388.
Sources: Calendar of Inquisitions Post Mortem 1361-65, nos. 118, 299; Calendar of Close Rolls 1360-64, pp. 201-11.