Why is gift-giving so important as aspect of Chanukah?
Gift-giving was a part of the early Purim tradition, but not of the Chanukah tradition. In Eastern Europe, on the fifth night of Chanukah families gathered for a special family night during which children were given Chanukah gelt (Chanukah money).
Later, when Christians and Jews mingled more freely, Jews were influenced by the Christian tradition of giving gifts to children at Christmas time.
Soon, Jewish parents began the practice of giving gifts other than Chanukah gelt to their children.