What are some of the failed invasions of England?

[GorillaMan]

@Roches

Hitler’s planned invasion (Operation Sealion; see the link for an essay on why it wouldn’t work) was little more than a plan, a plan that would have been difficult if not impossible to pull off. …Suffice it to say that it was a planned invasion that was never attempted, so I don’t think it counts as a failed invasion.

The OP may on the other hand be talking about the urban myth of the failed Shingle Street landing. Which also doesn’t count as a failed invasion, because it never happened.