Historical tradition associates Conall with the Sligo–Leitrim area, which certainly fits early Uí Néill expansion northwards from a Connacht homeland. He is credited with feats of running on Benn Gulban (Benbulben, Co. Sligo), while still a youth, which earned him his sobriquet. Allegedly, he was tutored by Muiredach Menn, local ruler of Calraige (in north Co. Sligo), whose murder by the Ulstermen prompted him to take a leading role in the conquest of the north-west. It certainly seems that a territorial expropriation of the Co. Donegal area by Conall, or his progeny, took place at an early date, as a lack of tributary kingships in that district suggests. Against this geographical background, the story of his death at the hands of raiders from Masraige (Co. Leitrim) is not implausible.
Clearly, a belief in Conall's importance persisted; according to the so-called ‘Timna Néill’ (the testimony of Niall), his father bequeathed the sovereignty to Conall – presumably to be equated with Conall Gulban, as another verse has Niall leave his ‘primacy’ to Crimthann. Yet Conall is not included in the regnal lists of the kings of Tara. Nonetheless, he maintained an importance in later historical tradition: a sixteenth-century romance, ‘Eachtra Chonaill Gulban’, has him fighting for the Holy Roman Emperor on the Continent and in the Middle East, while the kingship is held by his alleged brother, Lóegaire. Two of Conall's great-grandsons, Ainmere (d. 569) and Báetán (qv) (d. 581) achieved political distinction; the king of Tara, Diarmait (qv) son of Cerball son of Fergus, was perhaps a grandson.