The word “Easter” comes from an ancient pagan goddess worshipped by Anglo Saxons named Eostre. According to legend, Eostre once saved a bird whose wings had frozen during the winter by turning it into a rabbit. Because the rabbit had once been a bird, it could still lay eggs, and that rabbit became our Easter Bunny. Eggs were a symbol of fertility in part because they used to be so scarce during the winter. There are records of people giving each other decorated eggs at Easter as far back as the 11th century.
The Writer’s Almanac (2007)