The Knights of the Round Table are the legendary knights of the fellowship of King Arthur that first appeared in the Matter of Britain literature in the mid-12th century. The Knights are an order dedicated to ensuring the peace of Arthur's kingdom following an early warring period, entrusted in later years to undergo a mystical quest for the Holy Grail. The Round Table at which they meet is a symbol of the equality of its members, who range from sovereign royals to minor nobles.

Source: Wikipedia