But who, really, was Lambert Simnel? According to wikipedia and all the other obvious online sources he was an impostor, a poor boy who was made a Yorkist tool. He had been picked up by a priest named Richard Simon who thought he looked enough like Edward IV to pass as one of his missing sons, the Princes in the Tower. Simon trained the boy how to act like a nobleman. Simon then introduced the boy to John de la Pole, the Earl of Lincoln, who made him the focal point of the rebellion. After the rebellion, Henry "realised that Simnel was merely a puppet for the leading Yorkists" and pardoned him, offering him a job in the royal kitchens.
Henry VII and Two of his Advisers
But where does this information come from? From Henry's government. Absolutely every account about the supposed "true" identity of Lambert Simnel comes from a Tudor source, and most of them relied on a royal inquest convened in the wake of the failed rebellion.
Now maybe the published findings of the inquest were true; but how would we know? If the Yorkists had been victorious at Stoke Field – which they might well have, it was a near-run thing – would anyone now believe that story, or would we consider it obvious propaganda from a desperate, failing regime? Can we really trust a Tudor inquest into the parentage of a rebel against them?
Here, I think, is a good litmus test for the attitude of historians toward our sources. Many historians, I suspect most, would say that we have good reasons for doubting the identity of the supposed Earl of Warwick. They would be very skeptical that the Tudors could have succeeded so well in painting the rebel as a poor fraud if he had really been a noble scion of Neville and York. Could royal propaganda really have convinced a whole nation of a completely untrue, made-up story about an important historical figure?
But no, answer the first group; history isn't something we make up as we go along, it is a record of what happened. Sometimes it is hard for us to figure out what happened, but it is also hard to fool us. We know about hundreds of plots, frauds, and conspiracies from times less well documented than England of the 1480s, and this should give us confidence that few plots or frauds make it into the records unquestioned. A partisan tale may hold the field for a while – the Lost Cause, the Stab in the Back – but other sources always record alternative narratives, and by careful sifting we can work out which one is closest to the truth.
How naïve of you, answer the skeptics, to think that the truth always wins out in the end, or to think that history is such a wise and all-seeing goddess that she can never be fooled.