Ever wondered how Halloween started? Well, check the below history of Halloween infographics to understand more about the scary festival as the below Halloween infographics template suggests: the beginnings of Halloween trackback to an ancient, pre-Christian Celtic festival of the dead. The festival, Samhain, is the biggest and most significant holiday of the year and is celebrated on October 31st, marking the harvest season's end. The Celts believed that the dead returned to earth on Samhain, and they would gather together to light bonfires and sacrifice animals, fruits, and vegetables to honor the dead. The infographics also suggest that the Roman conquest began, and the Celts' lands were invaded. Sahamin is greatly affected by the spread of Christianity as Christian missionaries tried to subsume this pagan holiday under the celebration of the Church's martyrs and saints.