What is the history, and are there any special religious celebrations held on this day?
In the Roman Catholic Church, "All Saints Day" is a "Major Feast", more usually called a "Holyday of Obligation".
It is a day upon which "the faithful members of the Church" are under a strict obligation to do all that is reasonably possible to attend Mass - with perhaps even a greater degree of importance than attending Mass on the "Ordinary Sundays" of the year - all of which are themselves obligatory.
There is a specific laid down order of Mass for All Saints Day, with certain obligatory prayers and readings which are used in all Roman Catholic Churches on 1 Nov. every year (excepting that it is common practice for this to be celebrated on the nearest Sunday if 1 Nov is a Monday or Saturday).
In England and Wales, the Holydays of Obligation are:
Christmas Day; the Epiphany ( 6 Jan ); the Ascension (Thursday after the sixth Sunday of Easter - often described as 40 days after Easter); Corpus Christi (Thursday after Trinity Sunday); The Feast Day of Saints Peter and Paul ( 29 Jun ); the Assumption of the Blessed Virgin Mary ( 15 Aug ); and All Saints Day.
Other countries have some degree of freedom to vary the Holydays of Obligation to suit local custom and practice. I am not 100% certain that All Saints Day is observed as a Roman Catholic Holyday of Obligation in every country of the world, but it probably is.
Best wishes - Majikhise.
All Saints' Day according to the Roman Catholic Church officially the Solemnity of All Saints and also called All Hallows or Hallow-mas, often shortened to All Saints, is a solemnity celebrated on November first, by most parts of Western world, and on the first Sunday after Pentecost in Eastern world, in honor of all the saints, from all times, known or unknown. In the Western world it is the day after Halloween and the day before All Souls' Day. Halloween is also referred to as All Hallows Eve.
It's celebrating Jesus Christ, God and paying Thanks to the Saints in Heaven.
In the early days Christians celebrated a day to remember a martyr's death. When the death toll grew too big a special day was assigned to pay tribute to every saint's death.
They have a Feast for Saints.