Samhain began at sunset on 31 October, because the Gaelic day began at dusk, and it marked the end of the harvest and the start of the dark half of the year. It began in Ireland. Irish and Scottish emigrants carried its customs to North America in the 19th century, and America sent them back to the rest of the world as Halloween.
Largely, yes. Samhain, the Gaelic festival on 31 October to 1 November, originated in Ireland and was kept in Ireland, Scotland and the Isle of Man. Irish and Scottish emigrants carried its customs, guising, pranks and carved lanterns, to North America in the 19th century, and American Halloween spread them worldwide. The Christian All Hallows, kept on 1 November in Ireland by about 800, is the other half of the name and the story.
SOW-in, rhyming with 'cow-in'. In Irish it is written Samhain and means November; Halloween night is Oíche Shamhna.
Possibly, but it is not established. John Rhys and James Frazer proposed it in the late 19th century, and the historian Ronald Hutton calls the evidence flimsy.
Turnips and mangel-wurzels were what there was. In the 19th century they were hollowed, carved with faces and lit at Halloween in Ireland, Scotland, Wales and England. Emigrants in America used the pumpkin instead because it is larger and softer.
A fruit loaf with objects baked in: a ring meant marriage within the year, a coin wealth, a pea no marriage that year, a stick a quarrelsome marriage, a rag bad luck. Shop bracks today contain only a toy ring.
Kept a Halloween custom in your family that is not here — a game, a food, what the children said at the door? Tell us.