"The name Death's-head Hawkmoth refers to any one of the three species (A. atropos, A. styx and A. lachesis) of moth in the genus Acherontia. The former species is primarily found in Europe, the latter two are Asian, and most uses of the common name refer to the European species. These moths are easily distinguishable by the vaguely skull-shaped pattern of markings on the thorax. All three species are fairly similar in size, coloration, and life cycle."
These moths have several unusual features. All three species have the ability to emit a loud squeak if irritated. The sound is produced by expelling air from the pharynx, often accompanied by flashing of the brightly-colored abdomen in a further attempt to deter predators. All three species are commonly observed raiding beehives of different species of honey bee for honey; A. atropos only attacks colonies of the well-known Western honey bee, Apis mellifera. They can move about in hives unmolested because they mimic the scent of the bees."
It's Large Elephant Hawk I think. I guess it was looking for somewhere to pupate - they burrow into the ground. It's favourite food is rosebay willow herb but I think they will also feed on fuschia. If you've still got it release it near some bare looose soil if there is any around. Otherwise somewhere near where you found it.