FYI for anyone seeking to download all their emails (or any other data stored by Google) they now have a handy tool developed at the behest of the EU: Google Takeout: https://takeout.google.com/
Google Takeout predates GDPR by several years. I'm not sure if there was any other legislation in place in 2011 that required Google to provide something like this. My recollection is that it was not directly related to any actual legislation at the time.