The newspaper was considered to be the Irish edition of the Mail on Sunday. However, this was not always the case. The newspaper was originally founded in 1996, by former County MeathGaelic football player Liam Hayes, as a sports-only newspaper, The Title. In 1997, it was expanded into a general broadsheet Sunday newspaper, under the name Ireland On Sunday, with Hayes as its editor. IoS (as it was nicknamed) was aimed at the traditional Irish nationalist readers who had formerly read The Sunday Press. The paper's columnists included Tim Pat Coogan and Niall O'Dowd. In 2000, the newspaper was sold to Scottish Radio Holdings; a year later, having switched to tabloid format, it was sold to Daily Mail and General Trust. Since then, it had been relaunched again, with a format similar to the Mail on Sunday.
On 21 September 2006, Associated Newspapers announced that the 17 September 2006 edition of Ireland on Sunday had been the newspaper's final edition, with its replacement with the Irish Mail on Sunday from 24 September. The newspaper had already been considered informally as the Mail on Sunday's Irish edition, however it was now officially an edition of the Mail on Sunday and use a variation of that newspaper's masthead and editorial style. The UK edition of the Mail on Sunday was withdrawn from the Irish market in line with this.