March Madness has arrived and WWE.com invites the WWE Universe to participate in a brand-new tournament to finally decide what faction is the greatest of all time. (View larger bracket)

We've selected factions including DX, The nWo and The Shield and pitted them against each other, leaving the outcome of each battle entirely in the hands of the WWE Universe.

Take a look at the match-ups and vote for your favorite factions in the polls below as they battle to be crowned the greatest faction of all time. The faction with the most votes in each respective match-up will advance to the next round, so vote wisely.

Round 1 voting ends this Monday when Round 2 begins.