"The Twins of Macha"
Modern: Fort Navan
, Co. Armagh
An iron-age fort in Ireland. The earliest mention of the place may be in the writings of Ptolemy's Geographia, where he mentions the Isamnion Promontory in the land of the Volunti, better known as the Ulaid who gave their name to Ulster. The area is believed to have been continuously inhabited from the end of the last Ice Age until 500 CE.
Archaeologists have determined that in 95 CE, a ceremonial structure--a circular house--was built inside the fort, which was then burned. The ashes were then buried over with dirt, which creats the present mound. The reasons for this even are unknown.
In Irish literature and legend, Emain Macha is the capitol of Ulster, and home to the court of King Conchobor mac Nessa. Like Arthur's Camelot, it functions as the starting place of many adventures. According to the epics, Conchobhor would hold a major feast there at each Samhain: "One hundred vats of every kind of drink were provided, and Conchubur's officers said that the excellence of the feast was such that all the chieftains of Ulaid would not be too many to attend." (Which sounds like one hell of a Halloween party.)
The origin of Emain Macha and why it is named as such is as follows:
Macha, wife of the farmer Crunnchu, is forced to race the horses of Conchobhor after her husband boasts of her speed. She is pregnant, but if she doesn't race, her husband will be killed. She races, wins, gives birth to twins, and dies. Her name is then attached to both the fort and the county (Ard Macha > Armagh).
Now, this Macha is part of the triple Macha, and represents the Third Function (fertility, the land) in the Dumezilian system of Indo-European Tripartition. As such, she is then a goddess of the land, and the abuse of her person causes the famous Debilitation of the Ulstermen, wherein they suffer birth pangs during the invasion by Connacht during the Táin Bó Cuailgne.