The flags of the Twelve Tribes of Israel were signs used to identify each leading prince. It is suggested in Numbers II:7 that these 12 flags were the precursor to the national flags that survive today. Each of the flags consisted of a color and a symbol.
The flag of the tribe of Reuben was red and featured the embroidered image of mandrakes. Simeon's was green, featuring an image of the town of Shechem. The tribe of Levi was represented by a tricolor flag with a black top third, a white center third and a red bottom third. On it was an image of the Urim and Thummim, a device used by high priests for divining oracles. The Judah flag was blue, like the "heavens," and featured the image of a lion. The flag of Issachar was black, featuring the sun and the moon. This was symbolic of the tribe's reputation for understanding "the times." The tribe of Zebulon was plain white with an image of the sea, referencing the passage in Genesis that described this tribe as shore-dwellers.
The Dan tribe was a sapphire-like color and featured a serpent. Gad's was a mixture of white and black and featured the image of troops. The tribe of Napthali is described as being the color of clarified wine, which is a kind of light red or purple, and featured the symbol of a hind. The Asher tribe was a pearl color with an olive tree symbol. There were two flags for the tribe of Joseph, one for each of the princes Ephraim and Manasseh. Both jet black, Ephraim's featured the image of a bullock, while Manasseh's featured a wild ox. Finally, the tribe of Benyamin combined all the other colors and featured a wolf, symbolic of Benyamin himself.