It was created on 1 January 1819 by Ferdinand I of the Two Sicilies to reward military valor and merit. It received its name to celebrate the reunification of the dominions located namely (Naples and Sicily) into one kingdom after the Congress of Vienna.
The Order is divided into eight Ranks:
The decoration is formed by: ruby enameled lilied cross with in the middle a white enameled round plate bearing the image of a mounted St. George running the dragon through with his sword, bordered by a circle of blue enamel with the inscription "IN HOC SIGNO VINCES" and a laurel wreath.
The decoration of the Knights of Grand Cross has a golden image of St. George hanging down from the lower arm of the cross; the Royal Crown tops it.