The answer to your question is Celebrates the Exodus, the freedom from slavery of the Children of Israel from ancient Egypt that followed the Ten Plagues.
<span>During the reign of the Roman Emperor Constantine the Great (306–337 AD),Christianity began to transition to the dominant religion of the Roman Empire. ... In 313, Constantine and Licinius issued the Edict of Milan decriminalizing Christian worship.</span>
It has made a big like a real big impact on my life today and it continues too