This (long!) article was inspired by my huge irritation a) that so many people still think the Braveheart story of William Wallace fathering Isabella of France's child is somehow factual - people hit this blog pretty well every day searching for it - and b) that the notion of Edward II not being the father of his own eldest child has so well and truly taken hold in the popular imagination. For examples, if you can stomach them, see here, here, here, here and here, and the novels cited below. Read them and weep. I cannot adequately express my annoyance that a man with an Oxford doctorate on Isabella (Paul Doherty) wrote a novel (Death of a King) in which Edward III's biological father is Roger Mortimer, which Doherty must know is absolute BS but chose to sex up his novel by including it anyway and thereby giving the notion spurious plausibility. Agh.
EDIT: Thanks to Susan Higginbotham for telling me about a very recent post claiming that Edward II may have been 'cuckolded' and not the father of his children, in the Yahoo group of the Richard III Society, no less. Check out Susan's excellent and elegant rebuttal.
Braveheart features the future King Edward II as a fairly major character, with Edward – in real life, an enormously strong, athletic and handsome man – caricatured as a useless feeble court fop whose lover is thrown out of a window and whose wife cuckolds him with William Wallace. There are countless historical inaccuracies in Braveheart, which have been well detailed elsewhere, and I won’t go into them here. I just want to focus on one: the statement at the end of the film that Wallace is the real father of the baby Edward’s wife Isabella is carrying, who is, presumably, intended to be Isabella’s first-born child King Edward III.
Let’s check some basic dates and facts here:
- Sir William Wallace was executed on 23 August 1305.
- Isabella of France arrived in England on 7 February 1308, having married King Edward II at Boulogne on 25 January.  She had recently turned twelve at the time of her marriage and arrival in her new husband’s kingdom; her biographer* places her date of birth sometime during the winter of 1295/96.  (Edward II was born on 25 April 1284, so was about eleven and a half years his wife’s senior.) Isabella never met her husband’s father Edward I (‘Longshanks’), who had died on 7 July 1307 – not, incidentally, on the same day as Wallace, as depicted in Braveheart. She was never princess of Wales, as she married Edward II after his accession to the throne and became queen of England on marriage.
* Paul Doherty, but this is a properly-researched academic article, not a sensationalist, hopelessly inaccurate novel.
- Isabella’s first child, the future Edward III, was born at Windsor on 13 November 1312, more than seven years after William Wallace’s death. As noted above, Isabella’s date of birth means that she was nine at the time of Wallace’s execution, and was still in France at the court of her father Philippe IV. She was seventeen or shortly to turn seventeen at the time of her eldest child’s birth.
- Edward II and Isabella of France had four children together, not one, the others being: John of Eltham, earl of Cornwall (15 August 1316-13 September 1336); Eleanor of Woodstock, duchess of Gelderland (18 June 1318-22 April 1355); Joan of the Tower, queen of Scotland (5 July 1321-7 September 1362). In addition, Isabella may have suffered a miscarriage in or shortly before November 1313, when pennyroyal was purchased for her (though this is disputed). 
- Edward and Isabella had been married exactly nineteen years when the king was forced to abdicate in favour of their son, following Isabella and Roger Mortimer’s invasion of his kingdom; the fourteen-year-old’s reign as Edward III began on 25 January 1327. I make this point because there is a widespread misapprehension that Isabella overthrew her husband and ruled with Mortimer while her son – presumed to be her only child – was still only a toddler.
A few writers, both in novels and online, have realised the impossibility of William Wallace’s fathering Edward III, but have unfortunately taken on board the notion that Isabella of France took a lover and have looked around for another possible father for her son. This desperation to re-assign Edward III’s paternity appears to be based on the assumptions that a) Edward II was gay and therefore incapable of intercourse with women, and b) Isabella began a relationship with Sir Roger Mortimer, lord of Wigmore in late 1325, and therefore may well have committed adultery with him or another man a few years earlier. The first ever suggestion that Edward III was not Edward II’s biological son is found in Paul Doherty’s novel Death Of A King, published in 1982 – 670 years after Edward III’s birth. Doherty changes Edward III’s date of birth by eight months, from November 1312 to March that year, in order to put forward the theory that Roger Mortimer was the boy’s real father. In fact, it is physically impossible for Mortimer to have fathered Edward III, as he was in Ireland, a country Isabella never visited, at the time of the boy’s conception in February/March 1312. Mortimer was also in Ireland in the summer of 1311 nine months before March 1312, which puts paid to Doherty’s fictional theory, in Ireland in late 1315 and autumn 1317 when Edward and Isabella conceived their next two children, and on his way from Ireland to Herefordshire when their youngest was conceived in autumn 1320 (Isabella was at Westminster).  The notion that Roger Mortimer was Edward III’s biological father is also advanced in Charles Randolph Bruce and Carolyn Hale Bruce’s 2006 novel Bannok Burn, although Isabella manages to convince Edward that his own lover Piers Gaveston is the father. There is nothing at all to indicate that Isabella and Roger Mortimer had any kind of relationship – beyond the normal courtly association of a baron and his queen – before late 1325. Edith Felber’s 2006 novel Queen of Shadows has Edward III being fathered by a Scotsman who is never identified, with whom Isabella has an affair when she is ‘abandoned behind enemy lines’ in Scotland by her husband. In reality, Isabella never set foot in Scotland, unless you count the port of Berwick-on-Tweed, which was in English hands anyway when she was there in 1311 and 1314.
Let me just repeat the salient point here for absolute clarity: Roger Mortimer was in Ireland and thus several hundred miles away from Isabella at the time of Edward III's conception.
A comparison of Edward II and Isabella of France’s itineraries proves conclusively that they were together approximately nine months before the births of all their offspring. This will come as no surprise to anyone who does the inhabitants of early fourteenth-century England the credit of assuming that they weren’t so stupid and ignorant they wouldn’t have noticed anything amiss if the queen had become pregnant while she and the king were apart for months on end. (Which, incidentally, Edward and Isabella very seldom were.) Let’s take a look at the date of conception of their eldest child, Edward III. Edward II arrived in York in mid-January 1312 to meet up with Piers Gaveston, who had recently returned from his third exile, presumably to see his new-born child (Piers’ wife, Edward II’s niece Margaret de Clare, gave birth to his daughter Joan on or around 12 January 1312). In York on 20 February, after Margaret’s churching, Edward and the proud parents celebrated Joan’s birth with music and feasting.  Meanwhile, Queen Isabella was making her way north from Westminster to join her husband, remaining in frequent contact with him via her messenger John Moigne and sending him a basket of lampreys.  (The queen was certainly not "fraternising with the rebel barons on her way north to meet her husband" with the result that "Some doubt could be raised as to whether King Edward II was the genetic father of Prince Edward" as this silly page claims.) Edward III was born on Monday 13 November 1312. Counting back thirty-eight weeks from 13 November, roughly the length of a full-term pregnancy from the time of conception, brings us to 21 February (1312 was a leap year). On this date, Isabella’s Household Book shows her to have been at Bishopthorpe, just south of York, and she probably arrived in the city very soon afterwards.  The king and queen remained together in the city until early April. Easter Sunday fell on 26 March in 1312, so Edward and Isabella must have conceived their son during Lent, when intercourse was forbidden. This hardly lends credence to the notion that Edward slept with his wife unwillingly; Lent gave him the perfect excuse not to have sex with Isabella, if he didn’t want to.
The same applies to the conception of the couple’s younger three children: in November 1315, they were together at the royal hunting lodge at Clipstone in Nottinghamshire to conceive their second son John, born August 1316. In September 1317, they were together in York to conceive their daughter Eleanor, born June 1318. In October 1320, they were together at Westminster to conceive their daughter Joan, born July 1321. No record of the fourteenth century – not a single one – gives even the slightest hint that anyone believed Isabella had taken a lover and that Edward was not the real father of the future Edward III or of any of their other children. Privacy is a modern invention, and Isabella probably had less of it than anyone else in the country; she spent every minute of every day surrounded by ladies-in-waiting, damsels, chamber and wardrobe staff, and many other servants, and it is basically impossible that she could have conducted an affair and kept it secret (two of her sisters-in-law in France had affairs, but were discovered and imprisoned and their lovers executed). The purity of royal and noble women and the sacred royal line were considered of vital importance, and it is unlikely that Isabella ever had much, if any, chance to be alone with a man who wasn’t a close relative. People who believe that she took a lover in early 1312 who fathered her son – and bear in mind that the queen was only sixteen years old then – must explain how she managed this seemingly impossible feat without anyone ever noticing. Her relationship with Roger Mortimer, whatever the true nature of it was, began in late 1325 and occurred when she was in France and beyond Edward’s influence, after their marriage had broken down and long after she had borne her husband’s children. This cannot be taken to mean that Mortimer, or anyone else, had been her lover years before.
It was only in the late twentieth century that speculations about Edward III’s paternity arose, presumably on the basis that Edward II was gay and therefore incapable of intercourse with women. Although it is beyond doubt that Edward II loved men, he had an illegitimate son called Adam, so evidently wasn’t repelled by sex with women and might have enjoyed it enormously for all we know. Adam, sadly, is very obscure. The identity of his mother is unknown, his date of birth likewise, though a date of sometime between about 1305 and 1308 (when Edward II was twenty-one to twenty-four) seems likely. The boy or young man, called ‘Adam, bastard son of the lord king’ (Ade filio domini Regis bastardo) and ‘Adam, son of the king’ (Ade filio Regis) accompanied his father on the disastrous Scottish campaign of September/October 1322 with his tutor Hugh Chastilloun, and was given money totalling thirteen pounds and twenty-two pence to buy himself ‘equipment and other necessaries’. He is probably, rather than his younger half-brother the future Edward III, the boy called ‘the king’s son’ in a letter sent to Edward II in the summer of 1322, wherein the unidentified writer comments that “all good qualities and honour are increasing in him” (tutes bountes e honours sount en lui cressaunt). Adam died shortly before 30 September 1322, probably in his mid-teens or thereabouts, and was buried at Tynemouth Priory; his father bought a silk cloth with gold thread to lie over his body.  For the record, Piers Gaveston fathered an illegitimate daughter called Amie, as well as his legitimate daughter and heiress, Joan. 
Although writers who push the ‘Isabella took a lover who fathered her child’ narrative probably think otherwise, they’re actually doing her a gross insult, not to mention pushing a ludicrously anachronistic notion of sexual freedom for royal women in the Middle Ages. (Fictional depictions of the queen of England managing to have hot sex with Roger Mortimer without anyone ever noticing by escaping from court wearing a Harry Potter-style invisibility cloak, I mean a hood: I point at you and mock.) Isabella, daughter of the king of France and the queen of Navarre, sister of three kings of France and herself crowned queen of England at the age of twelve, was a woman with (understandably) a powerful and sacred sense of her own royalty and exalted status. In 1314, two of her brothers’ wives were found to have committed adultery and imprisoned; according to several chronicles, it was Isabella herself, visiting Paris, who informed her father Philippe IV of the women’s actions. If true, this was almost certainly not intended vindictively or maliciously, but demonstrates Isabella’s concern that her sisters-in-law might become pregnant by their lovers and thereby endanger the French royal line. In 1329, when her son Edward III had to pay homage for his lands in France to her cousin Philippe VI (son of Philippe IV’s brother the count of Valois and first of the Valois kings of France), Isabella declared furiously “The son of a king would never do homage to the son of a mere count.”  In 1318, when the impostor John of Powderham claimed to be the rightful son of Edward I and to have been switched in infancy for a peasant boy, the rumours spreading through the kingdom "annoyed the queen unspeakably."  (Not that she believed the story, I'm sure, but it must have been deeply humiliating for Isabella to have half the country speculating that her husband was not the descendant of kings but a peasant.) Does any of this sound even remotely like a woman who would have taken a non-royal lover and foisted his child onto the English throne?
Whatever the nature of Edward II’s sexuality and whatever his contemporaries thought of it, no-one doubted that he fathered Isabella’s children – let me repeat that there is not the slightest hint in any medieval source or anything written prior to the 1980s to suggest that anyone thought he didn’t – and therefore there is no reason for us to doubt it. Edward himself certainly never doubted that his children were his; there are numerous indications that he loved them deeply, rejoiced at their births and took great pride in them. No historian worth his or her salt would ever write that Edward did not father Isabella’s children, so if you see this claim anywhere, be aware that the writer hasn't a clue what s/he is going on about.
1) Elizabeth Hallam, The Itinerary of Edward II and His Household, 1307-1328 (List and Index Society Publications, 211, 1984), pp. 27-28; Calendar of Fine Rolls 1307-1319, p. 14.
2) Paul Doherty, ‘The Date of Birth of Isabella, Queen of England’, Bulletin of the Institute of Historical Research, 48 (1975), pp. 246-248.
3) G.E. Trease, ‘The Spicers and Apothecaries of the Royal Household in the reigns of Edward I and Edward II’, Nottingham Medieval Studies, 3 (1959), p. 46.
4) Ian Mortimer, The Greatest Traitor: The Life of Sir Roger Mortimer (2003), pp. 49-50, 69-70, 87, 100-01, 305-310.
5) Gesta Edwardi de Carnarvon Auctore Canonico Bridlingtoniensi, in W. Stubbs, ed., Chronicles of the Reigns of Edward I and Edward II, volume 2 (1883), p. 42; Pierre Chaplais, Piers Gaveston: Edward II’s Adoptive Brother (1994), pp. 78-79; J.S. Hamilton, Piers Gaveston, Earl of Cornwall 1307-1312: Politics and Patronage in the Reign of Edward II (1988), pp. 93-94; Constance Bullock-Davies, A Register of Royal and Baronial Domestic Minstrels 1272-1327, p. 143.
6) F.D. Blackley and G. Hermansen, eds., The Household Book of Queen Isabella of England 1311-1312 (1971), pp. 25, 27, 137, 143.
7) Ibid., p. 13.
8) F.D. Blackley, ‘Adam, the Bastard Son of Edward II’, Bulletin of the Institute of Historical Research, 37 (1964), pp. 76-77; Seymour Phillips, Edward II (2010), pp. 428-429.
9) The archives of soc.genealogy.medieval are chock-full of threads about Amie.
10) Cited in Ian Mortimer, The Perfect King: The Life of Edward III (2006), pp. 73-74.
11) Vita Edwardi Secundi, ed. N. Denholm-Young, p. 86.