The League was the main base of support for the Irish Parliamentary Party (IPP), and under Parnell's leadership, it grew quickly to over 1,000 branches throughout the island.
[1] In December 1890, both the INL and the IPP split on the issues of Parnell's long standing family relationship with Katharine O'Shea, the earlier separated wife of a fellow MP, Capt.
The National League maintained a code based on the writings of Young Irelander James Fintan Lalor which regulated transactions relating to the land.
[3] The key provisions forbade paying rent without abatements, taking over land from which a tenant had been evicted, and purchasing their holding under the 1885 Ashbourne Act.
[2] Other forbidden actions included "participating in evictions, fraternizing with, or entering into, commerce with anyone who did; or working for, hiring, letting land from, or socializing with, boycotted person".