O’Connell launched Repeal in 1840 after parliamentary influence failed to win Irish self-government

Evidence

O’Connell had organized the Loyal National Repeal Association—its name an exact expression of its character—on April 15, 1840, with an initial membership of fifteen. A decade in parliament, during which time the Irish party had on occasion held the balance of power between Whigs and Tories, had failed to win either to embrace self-government for Ireland. Now O’Connell had decided that the time was ripe to launch a campaign for home rule relying on the methods of peaceful agitation that had proved so successful in winning Catholic Emancipation. — Noel Ignatiev, How the Irish Became White, 68