Question

Why was John Hancock’s signature on the Declaration important?

Answer 1

His signature was important because he was president of congress when the Declaration of Independence was adopted and signed. hope this helps:)

Answer 2

It wasn't

While many stories have popped up trying to explain why his signature was so big, such as Hancock's desire to have the signature be big enough for the King to read it, etc. these are all fake stories and no one knows why it was so big.

While he was President of the Congress, it does not explain the size of his signature.