Tuatha de Danaan

The Tuatha de Danaan are a humanoid race of extradimensional beings that hale from Avalon, a small pocket-dimension adjacent to Earth. An interdimensional nexus between Avalon and Earth can be reached via the United Kingdom. They are also known as the Celtic Gods, who have been worshiped by the Celts (a civilization of humans who lived in the British Isles and regions of Europe). The worship of the gods fell with the rise of Christianity.