ope boniface iv designated november 1 all saints' day, a time to honor saints and martyrs. it is widely believed today that the pope was attempting to replace the celtic festival of the dead with a related, but churchsanctioned holiday. the celebration was also called allhallows or allhallowmas (from middle english alholowmesse meaning all saints' day) and the night before it, the night of samhain, began to be called allhallows eve and, eventually, halloween. even later, in a.d. 1000, the church would make november 2 all souls' day, a day to honor the dead. it was celebrated similarly to samhain, with big bonfires, parades, and dressing up in costumes as saints, angels, and devils. together, the three celebrations, the eve of all saints', all saints', and all souls', were called hallowmas.