For a holiday that is supposed to be about rebirth of Christ, it seems odd that the holiday has become so associated with candy, rabbits and eggs. Coming at the end of Lent, most people think of Easter as a firmly religious holiday that has a totally secular bent to it. The truth behind it is that Easter is a Pagan holiday/festival that was absorbed into the Christian faith and later absorbed into secular society.
Easter was originally celebrated two days after Passover, so it would arrive any day of the week given the year. It wasn’t until 338 when Emperor Constantine declared that the day would happen on Sunday that the day was given a solid date. More than that, the name “Easter” has little to do with Christianity. Easter loosely correlates to the old Germanic word for dawn, and more than that, to the goddess of the dawn. Eostre was the Pagan goddess heavily associated with Spring and Fertility, and festivals for her were held roughly around mid April. The holiday slowly distanced itself further and further from the original traditional meaning and timing.
As for why we have eggs, the egg has long been an incredibly important object in religion and culture because of its miraculous ability to bring forth life from a lifeless container. Originally, Christians were thought to have painted eggs red, allowing them to signify both the blood of Christ and his escape from the tomb at the Resurrection. Another reason why the egg may have become integrally linked to Easter was that the Church forbid the consumption of eggs during lent, so the day lent ended (Easter) would be marked by a moment when people were allowed to chow down on them without God frowning.
With time, other symbols got added to the holiday (Eostre was said to have a small horde of bunnies who carried the light of dawn across the sky) and the Hare got permanently tangled into the mythos of the Easter holiday. Hares were long thought to be hermaphrodites who represented fertility and life; so their connection to the holiday that represented fertility and life was a short stretch. In the 1700s, German families in America told their children that they would be visited by the “Oschter Hase” if they were good and it would lay brightly colored eggs for the good children. Kids would build small nests for the Rabbit to lay its eggs in and over time, that evolved into egg hunts and baskets full of candies. Jelly beans and chocolate eggs made their break into the holiday tradition in the early 1800s (and the 1930s for the Jelly beans) in large part simply because of their shape. Easter shaped candy is a multi-billion dollar business these days simply because of the raw expenditure on sweets.
As a fun little parting tidbit, in other parts of the world, the Easter Bunny is not necessarily a bunny. Australia has the Easter Bilby (kinda looks like a ratsquirrelmouse) while Germany has everything from the Easter Fox to the Easter Stork. Some kids even get eggs delivered by an Easter Cuckoo.
Citations; eggcelence in reference: