Henry VIII vs daughter Mary was more than a family disagreement—it was a dangerous standoff with life-or-death stakes. In 1536, Mary Tudor refused to acknowledge her father’s authority as Supreme Head of the Church of England, defying both royal will and religious reform. Her refusal to sign the Oath of Supremacy put her in the same perilous position as others who had gone to the scaffold for less. Once his cherished daughter, Mary had become a political liability.
This episode explores just how close Henry came to executing his own child—and why Mary ultimately chose submission over martyrdom.
Transcription of Henry VIII vs. Mary: How Close Did He Come to Executing Her?
Something exciting is happening, which is that Wolf Hall: The Mirror and the Light is on in the US, finally. So I actually did back in November and December when it was on in the UK, I did a series of reaction videos and breakdowns and things like that.
But I’m gonna do another set looking at different topics just because it is so popular. I’m watching it again. It’s so amazing. Just like the books, everything about Wolf Hall is just the best.
When I was doing this first video reaction back in November, which seemed like such a long time ago, I looked at the execution scene of Anne Boleyn and how realistic was it.
I had this whole issue around them showing that Henry was getting married to Jane at the exact same time. I get it was for dramatic effect, but it was bad enough as it was. You didn’t have to make it exactly at the same time. Anyway, today I’m gonna talk about something different.
Which is the relationship between Henry and Mary, his daughter, and whether or not there was really any threat to Mary Tudor. So would Henry VIII really have killed his own daughter?
So in 1536 when the series starts, Mary Tudor was isolated. She was out of favor. She was refusing to take the Oath of Supremacy that named her father as the Head of the Church.
After Anne Boleyn‘s fall, Mary had hoped for reconciliation, but instead things actually wound up getting even more dangerous for her. So how close did she come to execution and would Henry have actually done it? Let’s discuss.
So Mary had suffered deeply duringAnne Boleyn’s rise. She’d been declared illegitimate, she’d been stripped off of her household. She was forcibly separated from her mother. Anne’s execution in May of 1536 seemed like it might change everything. Mary hoped that Henry would soften, maybe even restore her to the line of succession.
And certainly there were those, like the show shows, the Pole family who was hoping as well that she would get restored. But instead, Thomas Cromwell stepped in. He made it clear if Mary wanted peace, she’d have to submit not just to her father, but to his new role as the Supreme Head of the Church of England.
The political had become personal and Cromwell’s pressure campaign would push her to the brink. The Oath of Supremacy wasn’t just a signature, and this is what Bishop Fisher and Thomas More had found out. It was a renunciation, and that’s why they could not sign it in good conscience.
By taking the Oath of Supremacy, Mary would have had to deny the Pope’s authority and acknowledge Henry as the Head of the Church, and even worse, accept that her parents’ marriage had never been valid.
That meant calling herself a bastard, which for a devout Catholic, for the daughter of Katherine of Aragon, this wasn’t just painful, this was perilous to her spirit. To her, the Pope was God’s voice on earth. Signing the oath would be a betrayal of her conscience and her faith and her mother’s memory.
For a time, Mary refused and that refusal put her life in danger. Cromwell didn’t rely on subtlety. Mary was placed under a tight watch, denied visits from friends and allies, and bombarded with letters, insisting that she submit.
Some were laced with direct threats. If she refused, she could be tried for treason. And in 1536, treason meant death. Henry had already executed Thomas More and Bishop Fisher for refusing the same oath.
Anne Boleyn, his wife, had gone to the block just weeks earlier. Mary knew full well what her father was capable of. Cromwell told the Imperial Ambassador Eustace Chapuys that Mary’s stubbornness could cost her life. Was it a bluff? Some historians think so, but to marry isolated and frightened, the threat probably felt very, very real.
And she had every reason to believe that they would follow through. Would Henry have really crossed the line though? Few monarchs ever had, but not none.
Peter the Great of Russia, this was later, but Peter the Great of Russia would famously have his son Alexei, tortured and executed in 1718 for defying him. That was two centuries later, like I said. But it does show that there was sort of an idea that this could be done, that the monarch had to put monarch ideas before family ideas.
And then you look at even just within living memory, whoever killed the Princes in the Tower, if they were killed, I know that’s like its whole thing, but that somebody hurt those boys. Somebody threatened those boys, and I know it wasn’t their father, but it was their uncle, potentially. And I know people have ideas.
Again, I’m not trying to start like a whole Princes in the Tower thing. We have done that on this channel before. That’s not this, but just the idea that the precedent that killing young children, killing people who were innocent, who hadn’t even done anything, much less refusing an oath, it was there.
But in Tudor England, killing your own child would’ve been shocking and unprecedented. Killing your daughter wasn’t just cruel. It was politically dangerous. And in Mary’s case, it would’ve made her a Catholic martyr, infuriated Europe and possibly even triggered a war. But what was Henry even thinking?
Well, by the summer of 1536, he was determined to stamp out any opposition to his supremacy. Mary, once his beloved pearl of the world, which he called her, had become a liability. Her refusal to submit was a challenge to everything that Henry had built. But executing Mary also risked political backlash.
Henry likely saw her as a pawn, not a threat that he needed to eliminate. If she submitted, he won. If she didn’t, he might not flinch, but ideally she would break first. He didn’t need her blood, he needed her obedience. Cromwell’s job was to get it.
Had Henry executed Mary the fallout would’ve been immediate. Her cousin, Charles V ruled the Holy Roman Empire and was still furious about the treatment of Katherine of Aragon. Killing Mary could have sparked a war, or at the very least, drawn England deeper into isolation. Even Henry as bold as he was, had to consider how far he could push before Europe pushed back.
So was the threat real? Almost certainly. Would he have gone through with it? Maybe, but we’ll never know because Mary blinked first. She signed the submission with tears falling down her cheeks, her hand trembling. She saved her own life. It’s one of the few times that Henry didn’t have to choose between power and blood, but make no mistake, he came dangerously close.
So what do you think? Would Henry have actually killed his daughter?
Heather Teysko is the creator, writer, and producer of The Renaissance English History Podcast,  the original Tudor history podcast, started in 2009. She's been writing about history online for over 25 years, since her first site on Colonial American history became number one in history on Yahoo in 1998. In 2019 she created Tudorcon, which is now a yearly event, in addition to writing books, and running TudorFair.com - a whimsical Tudor Merch shop.
She has been passionate about Tudor England since she first read Alison Weir's The Six Wives of Henry VIII 30 years ago, and subsequently moved to London after college to spend her time immersed in Tudor history (how exciting when she got to interview Alison for the first time!). In addition to history, she is passionate about travel, and has lived in 3 countries and 4 states (not counting her perpetual state of confusion), and her family (who help her host her YouTube channel occasionally).
