Halloween is big here..

Halloween is historically popular in Scotland, although it's becoming even bigger with the US influence.
Here you can see a Halloween display in St Enoch's shopping mall for children. It's really scary.

FYI the name is Oidhche Shamach in Gaelic. Halloween is the last night of the Celtic year when the souls of the dead get to revisit the earth. The Romans incorporate the day into the Christian event All Souls Day. In northern Europe, on this day, flowers are often laid on the graves of deceased partners and lovers, so as the soul returns to the earth for the day, the first thing the experience are symbols of love - I think, a wonderful custom.