Connachta is the collective name for the dynasties that dominated the province of Connacht and claimed descent from a mythic figure named Conn Cetchath-ach. In the early historical period, the name applied only to the dynasties of Uf Ffachrach, Uf Briuin, and Uf Ailello, which shared a common fifth-century ancestor and were known collectively as na teora Connachta (the Three Connachta). Aside from legends and some scattered references in the early annals, very little is known about their origins and activities before the eighth century.
The Connachta of the prehistoric period are much celebrated in Irish myth and legend. Their perennial feuds with the Ulaid, which may have a basis in fact, provided the background for the Ulster Cycle, while some of their more famous kings, like Cormac mac Airt, became enshrined in the early Irish historical tales. Legend has it that they had lived in Ireland for centuries and had controlled much of the north, an area known as Leth Cuinn, from their ancient capitol at Cruachu on Mag nAf in County Roscommon. Some legends also connect them with Tara. Although their ultimate origins are not known, one story suggests that they came to Ireland from Spain in the distant past, under the leadership of Tuathal Techtmar, the grandfather of Conn.
Out of these legendary beginnings, the historical Connacht dynasties emerged in the course of the fifth and sixth centuries a.d. They are said to originate with three brothers named Ffachra, Bri’on, and Ailill, whose father, Eochaid Mugmedon, was king. Their activities are closely connected with those of their half-brother, Nfall Nofgfallach, who became the progenitor of their collateral kin, the Uf Neill. In the fifth century, it is claimed, all four siblings together with their families struck out in different directions, possibly from Mag nAf, and began the conquest of what was to become their historical homelands. Whatever the truth behind these events, the historical Connachta and Uf Neill did share a sense of common kinship. It is likely too that they originally recognized a joint over king, presumably the king of Tara, since there is little evidence for a separate provincial kingship of Connacht during this period. Exactly when the two groups finally parted ways is not clear, but it must have happened after the death of Ailill Molt (d. 482), apparently the last of the Connachta featured in the Tara kinglists.
During the fifth and sixth centuries, the descendants of Ffachra, Bri’on, and Ailill gained control of the best lands in Connacht and asserted their suzerainty over the local populations. These people included groups such as the Conmaicne, Partraige, Greccraige, Cfar-raige, Luigni, and Gailenga. For some time, though, they failed to gain ascendancy over the Uf Maine, a powerful kingdom in the southeast of the province. What evidence there is for this period suggests that the Uf Ffachrach were dominant, although they faced fierce competition from the Uf Briuin. The former had split early on into two main lines, the one controlling the northern coasts of the province, the other the southern border. The northern line consisted of four main septs that were collectively known as Uf Ffachrach in Tuaisceirt. These included the Uf Ffachrach Muaide on the river Moy; the Uf Ffachrach Muirsce in the north of County Sligo; the Uf Amolngada, the family of Tfrechan, in the north of County Mayo; and the Fir Cherai in west-central Mayo. The southern line lived along the Munster border and was known as Uf Ffachrach Aidne. They reached the height of their power in the seventh century under Guaire Aidne (d. 663), who later became a celebrated figure in Irish legend. But despite their early prominence, both the northern and southern lines were on the decline in the eighth century, and after the death of Donn Cothaid in 773, the Uf Ffachrach never again produced an over king of Connacht.
During this same period, the Uf Ailello enjoyed local autonomy in their lands north of Mag nAf, though they never played a major role in Connacht politics. In the eighth century, they ran into constant conflict with their subject peoples, the Luigni and Greccraige, and possibly also the expanding Uf Briuin. They were eventually wiped out at the battle of Ard Maicc Rimi in 792.
With the extinction of the Uf Ailello and the decline of the Uf Fiachrach, the kingship of Connacht from the late eighth century on became the sole prerogative of the Uf Briuin. In later centuries, their royal families would play a major role in Irish politics.
