One of the most widely known things about Bowie is that he had an extremely wide and eclectic taste in music. It's fairly apparent when it comes to his discography, which dabbles in genres from glam rock to electronic to industrial. That Bowie was a big fan of Elvis Presley, then, is hardly surprising. The two actually shared the same birthday, that being January 18th. Incidentally, this is the same date that Bowie's final album Blackstar released, an album which many theorists speculate Elvis holds the key to correctly interpreting. Specifically, an Elvis song recorded in 1960 titled Black Star. In the song, Presley details exactly what a Black Star is.
Every man has a black star A black star over his shoulder And when a man sees his black star He knows his time, his time has come
The song goes on to further describe a Black Star as a sign of looming death. As a massive Presley fan, it's entirely possible Bowie drew inspiration from this image while writing his final record.