Macha (Irish pronunciation: [ˈmaxə]) was a sovereignty goddess of ancient Ireland associated with the province of Ulster, particularly with the sites of Navan Fort (Eamhain Mhacha) and Armagh (Ard Mhacha), which are named after her. Several figures called Macha appear in Irish mythology and folklore, all believed to derive from the same goddess. She is said to be one of three sisters known as 'the three Morrígna'. Like other sovereignty goddesses, Macha is associated with the land, fertility, kingship, war and horses. The name is presumably derived from Proto-Celtic *makajā denoting "a plain" (genitive *makajās "of the plain"). It was also said that Macha was called Grian Banchure, the "Sun of Womanfolk".
A poem in the Lebor Gabála Érenn mentions Macha as one of the daughters of Partholón, leader of the first settlement of Ireland after the flood, although it records nothing about her.
Various sources record a second Macha as the wife of Nemed, leader of the second settlement of Ireland after the flood. She was the first of Nemed's people to die in Ireland – twelve years after their arrival according to Geoffrey Keating, twelve days after their arrival according to the Annals of the Four Masters. It is said that the hilltop where she was buried was named after her: Ard Mhacha, "Macha's high place". The surrounding woodland was cleared by Nemed's folk and named Magh Mhacha, "Macha's plain".
Macha, daughter of Ernmas, of the Tuatha Dé Danann, appears in many early sources. She is often mentioned together with her sisters, "Badb and Morrigu, whose name was Anand". The three (with varying names) are often considered a triple goddess associated with war.O'Mulconry's Glossary, a thirteenth-century compilation of glosses from medieval manuscripts preserved in the Yellow Book of Lecan, describes Macha as "one of the three morrígna" (the plural of Morrígan), and says the term Mesrad Machae, "the mast of Macha", refers to "the heads of men that have been slaughtered". A version of the same gloss in MS H.3.18 identifies Macha with Badb, calling the trio "raven women" who instigate battle. Keating explicitly calls them "goddesses", but medieval Irish tradition was keen to remove all trace of pre-Christian religion. Macha is said to have been killed by Balor during the battle with the Fomorians.