In Ancient Egypt, today would have been considered the birthday of Set or Seth in Ancient Calendar.
Set/Seth has an interesting back history. The most common stories about him pretty much lead down the road of killing his brother Osiris along with 72 other conspirators. However, many believe that this was not always the case. That once up a time, Set/Seth was a God many loved and adored and that it was the priests of Osiris whom eventually made him the fall guy.
Other theorists say he is linked to the same Seth/Set in the bible.
Sitchen wrote that Seth DID argue and war with Osiris because it was HIS right to inherit the throne of Egypt. When that right was taken away, it led to a war of the gods, so to speak.