Is Halloween celebrated in EH? Or something similar, like asking for bread in All Saints' Day?
Yes! Not that long ago - some of the oldest Basque people still remember -, Arimen Gaua (or Souls’ night) was usually celebrated around October 31st and November 1st-2nd, and it was related to All Saints’ Day. It's believed to be of Celtic origin just like Halloween or Samaín in Galiza.
Young people would take pumpkins and turnips from vegetable gardens, hollow them out, make some holes, and put some candles into them, then they would hang them at the crossroads to frighten people. Disguised using sheets and rags, young people walked around towns scaring their neighbours. In some places, they also went out asking for chestnuts, walnuts, and such. When the door opened they would say: Xanduli, Manduli, Kikirri!! Eman gozokiak guri!!! [Xanduli, Manduli, Kikirri!! Give us candies!!].
However, these traditions died out and nobody knows exactly why. Some people say it was the mandatory ultra Catholicism during Franco’s dictatorship that banned all these pagan remains - along with traditional masquerades, for example - and focused more on the mourning of All Saints’ Day. This day is very sad and serious in Spain, devoted to remember the dead and to go to the cemetery to bring flowers to the tombs, clean them, and such. Needless to say, in this gloomy ambiance the costumes, the scares and the laughters are a bit out of place.
However, as the number of Catholics goes down, the quicker this tradition fades away, and younger people prefer to import Halloween - a very much more festive celebration than All Saint’s Day - ignoring that we actually had our very own Halloween once! What we personally find problematic and sad about this festivity especially is that we’re not recovering our traditions and parties but are substituting them for Halloween.
But let's end this long answer on a bright note: traditional sweets to have around Arimen Gaua (they're not just limited to EH). Huesos de santo, literally, Saints' bones.
The outer part is marzipan, and the most traditional ones are stuffed with yolks mixed with sugar. There are other specialties stuffed with chocolate, and some others even include colourful marzipan. Believe us when we say they’re TOO sweet. Overwhelmingly sweet.
It’s believed that eating these bones is a way of showing love for the dead ones, instead of fear.
And also buñuelos: legend says that eating one buñuelo makes a soul leave the purgatory, so one should be very careful with these ridiculously-easy-to-eat ones, because you may want to start a crusade to get as many souls out of purgatory as possible, but it will also be a journey to having diabetes. Gotta be cautious.