What caused William Wallace's death?
Lack of breath.
The actual procedure used to execute Sir William Wallace was to
be 'hanged, drawn and quartered' and, according to Patwoods, "was a
punishment in mediaeval England and Ireland for English commoners
and any Scots, Irish or Welsh found guilty of high treason, until
it was abolished in 1814. The punishment was not removed from
Scottish law until 1947.
"It didn't apply to women (except in the Isle of Man) who were
more kindly dealt with by being burned alive at the stake until the
1790s, when they were hanged instead. Members of the English
nobility were also dealt with more mercifully, being beheaded.
"King Edward I (who Wallace fought against) is thought to have
come up with the idea when he needed to teach Wales a lesson by
causing his childhood companion, Daffyd, Prince of Wales, to be put
to death in 1283 in an especially nasty and memorable manner, for
turning against the English in general and his Majesty in
particular.
"How someone who isn't English could be convicted of treason
against the English has never been explained, though Scottish
William Wallace raised this question at his own trial for treason;
it did him no good, though.
"The punishment itself consisted of being dragged, or drawn,
naked on a wooden stretcher to the public execution area, where the
people would gather, some raucously following the criminals as they
were drawn through the streets. Food and beer was available for
sale and it was a big day out for all.
"On arrival at the public scaffold the traitor was hanged just
sufficiently to hurt a lot but not to actually die. Then his
genitals were cut off, he was disembowelled (with a special
disembowelling device), and the whole mess was burned where he
could see it close-up.
"He was then beheaded and his body cut into four parts, and
these five bits were stuck on poles or spikes, or otherwise hung
from a highly-visible place as a warning to others contemplating
treason. The head was simmered in salty water before display, so
the traitors face would remain recognizable.
"The execution of the Scot, William Wallace, in this manner was
lovingly detailed at the time in 1305. His four body parts went to
four different cities while his head (this time dipped in tar) was
stuck on London Bridge."