It was originally a Christian holiday, "all halows eve" but like with Christmas, excuse me, X-mas as PC people are supposed to say now. I hate it how people are trying to remove all Christian meaning from holidays, then they say Santa shouldn't be allowed because that is mixing church and state, when it was the idiot secular people that invented santa.I say we should abandon all religious meaning from Christmas, let it be a day when people waste money, and celebrate Jesus' birthday on another day. You know America spent 220 billion dollars this last Christmas? Imagine if instead of spending all that money we had given it to the poor, seems completely wiping out poverty would be a better way to spend Christmas than
sorry, pal - the pagan harvest festival called samhain (prn: "sow-wen") was swiped by missionaries plying their trade in Celtic Europe and "christianized"
Just as the date of what we of (Roman) Christendom (and, later, the Protestant derivatives) call "Christmas" was swiped and retrofitted from the Pagan Yule or Winter Solstice festival. Christ was not born on 25 December. IIRC the best chronologies place the date of birth in March.
Many "patron saints" are transmogrifications of elder gods and spirits - the attributes of these mythological entities became associated with celebrated Christian figures (some of whom definitely lived, others...?)
This was all a PR sell - switch creeds, keep the fun parties and minor deities under new names.
You may not like it, but facts are immune to such concerns.