Common ancestry with "Hamill" through Eochaidh BINNEACH. See History, #89.

89. Eochaidh BINNEACH
90. LAIRAN
91. DOMHNALL
92. ULTAN

Mac an ultais -VII-MacAnulty, MacKnulty, MacNulty, Nulty; 'son of the Ulidian' (or native of East Ulster, Ir.'?'); the name of a Donegal family, who are probably a branch of the O'Donlevys. (V. O Duinnpleive and Mac Duinnpleive). It is now common in Mayo and Meath. In the latter county, it is always angl. Nulty.
(From Edward McLysaght, G929.1415 M226ir)

MacNulty.
The derivation of many Irish surnames is open to doubt, but there is none about that of MacNulty: in Irish it is Mac an Ultaigh, i.e. son of the Ulsterman. An older anglicized form of the name, now rare, is MacAnulty. The MacNultys belong today as they have done since the inception of surnames, to northwest Ulster - to Donegal, which claims to be the most Irish part of Ireland. As might be expected from the location of this sept they were overshadowed by the O'Donnells, sometimes in association with them, as in the battle of Desertcreagh in 1281 (a MacNulty was among the "distinguished slain" there), sometimes against them as on the occasion in 1431 when the O'Donnells are recorded by the Four Masters as making a predatory expedition against the MacNultys of Tirhugh (Co. Donegal). From Derry, on the border of Co. Donegal, came Frank Joseph MacNulty (1872-1926), American labour leader, whose father Owen MacNulty was a veteran of the Civil War.

The name is also found in Co. Meath but always is shorn of its prefix Mac there. I presume these Nultys are an offshoot of the Donegal MacNultys. Bernard MacNulty (d. 1892), friend of John Boyle O'Reilly, was founder of the first branch of the Fenian Brotherhood in the U.S.A.