There is a connection here;
The three main cultures that deal with Giants - Biblical, Celtic and Norse. Prometheus exterior locations that are pretty much the same as they would be thousands of years ago - Jordan, the Scottish Highlands and Iceland. I'm beginning to wonder whether our giants of old were not the likes of big blue guy? Perhaps they were prisoners of war exiled (without weapons and technology) on Earth by their enemies (the saucer guys)? Or maybe their saucer crashed under the sea and they were unable to get to it to repair it? Discovering an interstellar craft, with navigational records, could explain how we are able to travel across the stars.
Perhaps we are going to see this backstory in Prometheus, a war-like race of giants dumped off on a backward planet with just puny humans to play with?