What is happening to William Wallace as he lays on the table at the end of Braveheart?

Nothing that is historically accurate. anyway. Sir William Wallace was a minor noble, not a scruffy tribesman as depicted in this film, and as such the records of his trial (if you could call it that) and execution were kept on record and still exist. He was dragged the three and a half miles from the Tower to Aldgate chained (not tied) to a piece of fencing, not on a wheeled cart, and he was never ‘racked’, just hanged vertically. He was never offered a chance to recant his beliefs in exchange for a quicker, more merciful death. While hanging, still alive, he was emasculated (‘his privy parts cut away’) and his genitals burnt on a brazier in front of him. The executioner then slit open his abdomen and disembowelled him, then his chest was cut open and his heart torn out. He was never allowed to speak, was not tied to a flat table and was beheaded after he was dead. The film gets all of this wrong.

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The torture was his sentence. He was Sentenced to Death by being ‘Hung, Drawn and Quartered. Courtesy of Wikipedia.

Convicts were fastened to a hurdle, or wooden panel, and drawn by horse to the place of execution, where they were hanged (almost to the point of death), emasculated, disembowelled, beheaded and quartered (chopped into four pieces).

As it is mentioned in the film, his four pieces were sent to the four corners of England / Scotland at the time to warn anyone else who thought about rising up from doing so. Not that it worked, Robert the Bruce came back and fought and won at the Battle of Bannockburn.

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