Father's Day was originally a pagan holiday, the Great Sky-Father's Day. Part of the week of celebrations leading up to the summer solstice, the day was give over to celebrating the Sky-Father's providing for his human children with his rich gifts of sun and rain. Gifts of sacrificial goats and sheep (recognizable by the festive ribbons bound about their necks) were supplemented with prayers for his continued guidance in the human journey towards spiritual adulthood.
The precise transition to the Father's Day we know today is lost in the mists of time, but it seems that several generations of Christian priests gradually attempted to neutralize the pagan rituals by focusing on the literal steps of the ceremonies, rather than their spirutual meanings. The passing of celebratory garlands from sons to fathers was retained, and reemphasized as the central act of the Great Sky-Father's celebration, rather than the sacrifices and prayers. As part of this reinterpretation, the practice of tying ribbons was moved from the animals to the fathers, and appears to be recognizably the origin of the custom of giving ties on Father's Day.