The Fairy Flag (Scottish Gaelic: Am Bratach Sìth) is an heirloom of the chiefs of Clan MacLeod. It is held in Dunvegan Castle along with other notable heirlooms, such as the Dunvegan Cup and Sir Rory Mor's Horn. The flag is made of silk, is yellow or brown in colour, and is a square of side about 18 inches (45 centimetres). It has been examined numerous times in the last two centuries, and its condition has somewhat deteriorated. It is ripped and tattered, and is considered to be extremely fragile. The flag is covered in small red "elf dots". In the early part of the 19th century, the flag was also marked with small crosses, but these have since disappeared. The silk of the flag has been stated to have originated in the Far East, and was therefore extremely precious, which led some to believe that the flag may have been an important relic of some sort. Others have attempted to associate the flag with the Crusades or even a raven banner, which was said to have been used by various Viking leaders in the British Isles.
There are numerous traditions and stories associated with the flag, most of which deal with its magical properties and mysterious origins. The flag is variously said to have originated as a gift from the fairies to an infant chieftain, as a gift to a chief from a departing fairy-lover, and as a reward for defeating an evil spirit. The various powers attributed to the Fairy Flag include: the ability to multiply a clan's military forces; the ability to save the lives of certain clanfolk; the ability to cure a plague on cattle; the ability to increase the chances of fertility; and the ability to bring herring into the loch at Dunvegan. Some traditions relate that if the flag were to be unfurled and waved more than three times, it would either vanish, or lose its powers forever.
Clan tradition, preserved in the early 19th century, tells how the Fairy Flag was entrusted to a family of hereditary standard bearers. Only the eldest male of this family was ever allowed to unfurl the flag; the first such hereditary standard bearer was given the honour of being buried inside the tomb of the chiefs, on the sacred isle of Iona. Tradition states that the flag was unfurled at several clan battles in the 15th and 16th centuries; the flag's magical powers are said to have won at least one of them. Another 19th-century tradition linked the flag to a prophecy which foretold the downfall of Clan MacLeod; but it also prophesied that, in the "far distant future", the clan would regain its power and raise its honour higher than ever before. In the mid-20th century, the Fairy Flag was said to have extinguished a fire at Dunvegan Castle, and to have given luck to servicemen flying bombing missions in the Second World War.