In Hoc Signo Vinces Key Ring

Emperor Constantine received a vision of this symbol and changed world history. "In Hoc Signo Vinces" translates from Latin as "In This Sign, Conquer." The ancient and traditional symbol of Catholicism is called the “Chi Rho” because Chi and Rho are the names of the first letters of the name of Christ as spelled out in Greek (ΧΡΙΣΤΟΣ, or Χριστός). This symbol is also sometimes called the Labarum.