All Saints Day in Spain always occurs the 1rst of November and is also known as All Hallows Day. It celebrates all the saints ever recorded.
Offerings are made on All Saints Day as a traditional celebration and honoring of the saints. It is a public holiday in Spain so office building and such are closed.
This holiday started when the Greek Christians kept a festival on the first Sunday after Pentecost which celebrates all martyrs and saints. Pope Gregory IV officially made it a holiday and changed the named to all saints day.