Its leader, Charles Stewart Parnell, had been cited as co-respondent in a divorce case, which he had not contested, causing a scandal.
A majority of the party's MPs left to form the Irish National Federation, a new Anti-Parnellite group.
The contest at North Sligo was the second of three by-elections which followed the split and gave the voters an opportunity to express their views of the two sides - as Callanan puts it, "a staggered plebiscite on [Parnell's] leadership".
[1] Clerical opposition to Parnell was strong, with two of the bishops whose dioceses covered parts of the constituency taking a firm anti-Parnell line.
But in Tireragh, in the west around the part of Ballina in County Sligo, Parnellite support was strong and the Bishop of Killala, whose diocese included the town, took a neutral line and allowed local priests to canvass for Parnell.