Possibly the first house erected within the site was that of a Sir William Blake, around 1624. The next owner was Lord Goring, who from 1633 extended Blake's house, which came to be known as Goring House, and developed much of today's garden, then known as Goring Great Garden. He did not, however, obtain the freehold interest in the mulberry garden. Unbeknown to Goring, in 1640 the document "failed to pass the Great Seal before Charles I fled London, which it needed to do for legal execution". It was this critical omission that would help the British royal family regain the freehold under George III.