I've been asked to explain these two celebrations. (scroll down for my Goal Post)
First off, neither of them are "Catholic traditions". Just like Lent they are Christian and come from Biblical origins. --Well, Ash Wednesday does anyway, Mardi Gras is a reaction to Ash Wednesday...but we'll get there later--
Protestant churches celebrate Ash Wednesday also, for example, all the Methodist churches I've been to as an adult had an Ash Wednesday service with the placing of ashes on the forehead in the shape of a cross.
To help understand Ash Wednesday I will take a couple quotes from this very good article that my Subvet found for me. (Thanks Hon!) This article was written by Fr. Saunders and I encourage you to go and read the whole thing for a more detailed history of Ash Wednesday.
Fr. Saunders is pastor of Our Lady of Hope Parish in Potomac Falls and a professor of catechetics and theology at Notre Dame Graduate School in Alexandria.
Copyright ©2005 Arlington Catholic Herald. All rights reserved.
Ash Wednesday is the beginning of Lent. Which is to say, it's the celebration that marks the beginning of our time of fasting and sacrifice known as Lent. As we move from "business as usual" into our time of remembering Jesus' sacrifice for us we also remember how we are undeserving of that sacrifice because of our sin.
The use of ashes originates in Old Testament times. Ashes symbolized mourning, mortality and penance. You can see them used in Book of Esther by Mordicai, also by Job, Daniel and the people of Nineveh (after Jonah finally showed up).
Since the Middle Ages at least, the Church has used ashes to mark the beginning of the penitential season of Lent, when we remember our mortality and mourn for our sins.
In our present Ash Wednesday liturgy [service] , we use ashes made from burned palm branches distributed on the Palm Sunday of the previous year. The priest blesses the ashes and imposes them on the foreheads of the faithful, making the sign of the cross and saying, "Remember, man you are dust and to dust you shall return," or "Turn away from sin and be faithful to the Gospel." As we begin this holy season of Lent in preparation for Easter, we must remember the significance of the ashes we have received: We mourn and do penance for our sins. We again convert our hearts to the Lord, who suffered, died and rose for our salvation. We renew the promises made at our baptism, when we died to an old life and rose to a new life with Christ. Finally, mindful that the kingdom of this world passes away, we strive to live the kingdom of God now and look forward to its fulfillment in heaven. In essence, we die to ourselves, and rise to a new life in Christ.
You know, the whole "ashes to ashes, dust to dust"...which, by the way is scripture. See Genesis 3:19.
Knowing that Lent was a time of solmness, remembrance, and fasting, folks started having a huge feast on the night before Lent began. Which would be the night before Ash Wednesday. The reason was two-fold. Back in the day meat was forbidden during ALL of Lent, not just on Fridays and this was before refrigeration/deep freezers folks. So here we are...Lent's around the corner and we won't be able to eat meat for 40 days........ what are we gonna do with all this food in our kitchen? PARTY!! Invite the neighbors and let's chow down. And since I'm giving up chocolate for Lent I think I'll bake a huge chocolate cake to eat too!!
I don't know if it originated in Louisana or if New Orleans is just the biggest group of partiers. But this pre-Lent celebration came to be known as "Mardi Gras" which literally translates to "Fat Tuesday". Meaning you got as "fat" as you could on the Tuesday before the fast would begin on Ash Wednesday.
I'm not positive but I believe a lot of the breast baring and kissing of strangers etc is an outgrowth of people getting their last kicks in before Lent too. Oh, and alcohol plays a big part in any Louisana party. Remember too that South La has a very large Creole population, whose origins are in the Carribean. They brought their native religion (voodoo etc) with them and incorporated it into the Christian celebrations of the "New World". (as did all native peoples worldwide when Christianity was introduced). Some of the "traditions" of Mardi Gras have been derived from this pagan influence.
Today it has blown out of all proportion and reason and has become a totally secular event. I actually think there are parties and such that continue even AFTER Ash Wednesday...completely missing the point of the original celebration. I do know that the parades start a couple weeks before Ash Wednesday and the drunkenness rivals any Spring Break. I've never been to N.O. for Mardi Gras and I never plan to go. But my family and friends who have gone came back with quite a few entertaining stories....to say the least.
If you have any questions or any corrections or additions to this please leave them in the comments. If there's something you don't believe or want to discuss go ahead and leave that in the comment too. But please remember to be respectful of me and of each other during the discussion!