It just shows the power of the priests. He started out as Pharaoh Amenhotep I, the second king of the 18th Dynasty. But his many building projects were so popular that the priests elevated him to deity status upon his death.
And he proved very popular, with many festivals held in his honor each year. Most houses had a picture of him, depicted with black or blue skin to symbolize resurrection. Which must have been a real inspiration to budding builders of the time.
AMENHOTEP must be one of the very few Gods to have left his mortal remains behind for us to poke at — his mummified body was discovered in 1881 in very good condition.