Halloween is not an italian tradition. In recent years, thanks to the influence of American Tv series, “trick or treat” has become popular among italian kids.
The actual Italian traditions for those days are Ognissanti, or Tutti i Santi, ‘All the Saints’ day’, on November 1st and Il giorno dei Morti ‘All souls’ day’ on November 2nd.
Frate Angelico, La Chiesa militante (‘The Church Militant), 1423-24
Duccio di Buoninsegna, Maestà, detail, 1308
In Italy November 1st is a holiday, people go to the Church and meet family and friends. On November 2nd we remember our morti, visiting them, bringing candles and flowers.