Your account data is hard-deleted, there is no simple way to restore all the account information, see this post from Nick Craver for more detail:
On deletion (or destruction - user deletion + deleting posts, almost
always reserved for spammers) we nuke everything about the user, no
record just a line somewhere with a user ID in it, we don't even know
what your display name was, much less any private data (email, real
We've talked about recording this on delete/destroy in case a user
wants to come back, but we've punted on it until now for 2 reasons:
- There are likely complications we don't realize until we get into implementing this (recording merges taught me this one)
- We don't want the encourage the trigger-happy "delete me!" behavior in any way.
That's not to say we won't do it to make even the exceptions easier on
us, at some point it's likely (just as merges finally became a
necessity) the pain of manually reversing both of these is a
nightmare, trust me.
If you want to be deleted, that's fine by us - in most cases we're
sorry to see you go, but we'll respect your decision. However, when
you ask for deletion do understand that you're being deleted, and
getting any data back is not always possible - and even if it is, it's
a total pain in the ass for us, and time much better spent on
improving the site for everyone.
TL;DR version: don't expect your data to be restored (posts
associated, etc.) if you come back later, we simply don't have the
resources to keep doing that.
While SE might decide to spend the effort to manually reassociate your posts to your new account, they make no guarantee on that.