Origin
The Sentience of the Universe was the embodiment of life in the previous universe (similar to Eternity in the new universe). This was revealed to be the sixth personification of the multiverse. He is stated as the inventor of science and the builder of the junction to everywhere.
As the universe collapsed on itself, the Sentience found one of the last sentient beings alive. His name was Galen from the planet Taa.
Though their deaths were inevitable, the Sentience joined with Galan so they could be reborn in the new multiverse They formed a cosmic egg that would become the new universe. Upon it’s expansion, they were reborn as Galactus along with Eternity (the seventh personification of the multiverse), Death and the other cosmic abstracts.