Today's Halloween customs are thought to have been influenced by folk customs and beliefs from the Celtic-speaking countries, some of which are believed to have pagan roots.
Jack Santino, a folklorist, writes that "there was throughout Ireland an uneasy truce existing between customs and beliefs associated with Christianity and those associated with religions that were Irish before Christianity arrived".
Historian Nicholas Rogers, exploring the origins of Halloween, notes that while "some folklorists have detected its origins in the Roman feast of Pomona, the goddess of fruits and seeds, or in the festival of the dead called Parentalia, it is more typically linked to the Celtic festival of Samhain, which comes from the Old Irish for 'summer's end'."

Samhain (/ˈsɑːwɪn, ˈsaʊɪn/) was the first and most important of the four quarter days in the medieval Gaelic calendar and was celebrated on 31 October – 1 November in Ireland, Scotland and the Isle of Man.
A kindred festival was held at the same time of year by the Brittonic Celts, called Calan Gaeaf in Wales, Kalan Gwav in Cornwall and Kalan Goañv in Brittany; a name meaning "first day of winter".
For the Celts, the day ended and began at sunset; thus the festival began on the evening before 7 November by modern reckoning (the half point between equinox and solstice).
Samhain and Calan Gaeaf are mentioned in some of the earliest Irish and Welsh literature.
The names have been used by historians to refer to Celtic Halloween customs up until the 19th century, and are still the Gaelic and Welsh names for Halloween.

Samhain/Calan Gaeaf marked the end of the harvest season and beginning of winter or the 'darker half' of the year.
Like Beltane/Calan Mai, it was seen as a liminal time, when the boundary between this world and the Otherworld thinned.
This meant the Aos Sí (Connacht pronunciation /iːsˈʃiː/ eess-SHEE, Munster /e:s ʃi:/), the 'spirits' or 'fairies', could more easily come into this world and were particularly active.
Most scholars see the Aos Sí as "degraded versions of ancient gods [...] whose power remained active in the people's minds even after they had been officially replaced by later religious beliefs".
The Aos Sí were both respected and feared, with individuals often invoking the protection of God when approaching their dwellings.
At Samhain, it was believed that the Aos Sí needed to be propitiated to ensure that the people and their livestock survived the winter.
Offerings of food and drink, or portions of the crops, were left outside for the Aos Sí.
The souls of the dead were also said to revisit their homes seeking hospitality.
Places were set at the dinner table and by the fire to welcome them.
The belief that the souls of the dead return home on one night of the year and must be appeased seems to have ancient origins and is found in many cultures throughout the world.
In 19th century Ireland, "candles would be lit and prayers formally offered for the souls of the dead.
After this the eating, drinking, and games would begin".

Throughout Ireland and Britain, the household festivities included rituals and games intended to foretell one's future, especially regarding death and marriage.
Apples and nuts were often used in these divination rituals.
They included apple bobbing, nut roasting, scrying or mirror-gazing, pouring molten lead or egg whites into water, dream interpretation, and others.
Special bonfires were lit and there were rituals involving them.
Their flames, smoke and ashes were deemed to have protective and cleansing powers, and were also used for divination.
In some places, torches lit from the bonfire were carried sunwise around homes and fields to protect them.
It is suggested that the fires were a kind of imitative or sympathetic magic – they mimicked the Sun, helping the "powers of growth" and holding back the decay and darkness of winter.
In Scotland, these bonfires and divination games were banned by the church elders in some parishes.
In Wales, bonfires were lit to "prevent the souls of the dead from falling to earth".
Later, these bonfire
Today's Halloween customs are thought to have been influenced by folk customs and beliefs from the Celtic-speaking countries, some of which are believed to have pagan roots. Jack Santino, a folklorist, writes that "there was throughout Ireland an uneasy truce existing between customs and beliefs associated with Christianity and those associated with religions that were Irish before Christianity arrived". Historian Nicholas Rogers, exploring the origins of Halloween, notes that while "some folklorists have detected its origins in the Roman feast of Pomona, the goddess of fruits and seeds, or in the festival of the dead called Parentalia, it is more typically linked to the Celtic festival of Samhain, which comes from the Old Irish for 'summer's end'."
Samhain (/ˈsɑːwɪn, ˈsaʊɪn/) was the first and most important of the four quarter days in the medieval Gaelic calendar and was celebrated on 31 October – 1 November in Ireland, Scotland and the Isle of Man. A kindred festival was held at the same time of year by the Brittonic Celts, called Calan Gaeaf in Wales, Kalan Gwav in Cornwall and Kalan Goañv in Brittany; a name meaning "first day of winter". For the Celts, the day ended and began at sunset; thus the festival began on the evening before 7 November by modern reckoning (the half point between equinox and solstice). Samhain and Calan Gaeaf are mentioned in some of the earliest Irish and Welsh literature. The names have been used by historians to refer to Celtic Halloween customs up until the 19th century, and are still the Gaelic and Welsh names for Halloween.
Samhain/Calan Gaeaf marked the end of the harvest season and beginning of winter or the 'darker half' of the year. Like Beltane/Calan Mai, it was seen as a liminal time, when the boundary between this world and the Otherworld thinned. This meant the Aos Sí (Connacht pronunciation /iːsˈʃiː/ eess-SHEE, Munster /e:s ʃi:/), the 'spirits' or 'fairies', could more easily come into this world and were particularly active. Most scholars see the Aos Sí as "degraded versions of ancient gods [...] whose power remained active in the people's minds even after they had been officially replaced by later religious beliefs". The Aos Sí were both respected and feared, with individuals often invoking the protection of God when approaching their dwellings. At Samhain, it was believed that the Aos Sí needed to be propitiated to ensure that the people and their livestock survived the winter. Offerings of food and drink, or portions of the crops, were left outside for the Aos Sí. The souls of the dead were also said to revisit their homes seeking hospitality. Places were set at the dinner table and by the fire to welcome them. The belief that the souls of the dead return home on one night of the year and must be appeased seems to have ancient origins and is found in many cultures throughout the world. In 19th century Ireland, "candles would be lit and prayers formally offered for the souls of the dead. After this the eating, drinking, and games would begin".
Throughout Ireland and Britain, the household festivities included rituals and games intended to foretell one's future, especially regarding death and marriage. Apples and nuts were often used in these divination rituals. They included apple bobbing, nut roasting, scrying or mirror-gazing, pouring molten lead or egg whites into water, dream interpretation, and others. Special bonfires were lit and there were rituals involving them. Their flames, smoke and ashes were deemed to have protective and cleansing powers, and were also used for divination. In some places, torches lit from the bonfire were carried sunwise around homes and fields to protect them. It is suggested that the fires were a kind of imitative or sympathetic magic – they mimicked the Sun, helping the "powers of growth" and holding back the decay and darkness of winter. In Scotland, these bonfires and divination games were banned by the church elders in some parishes. In Wales, bonfires were lit to "prevent the souls of the dead from falling to earth". Later, these bonfire
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