foundation of the Gaelic Athletic Association and the growth in the performance of plays about Ireland in English, by playwrights including W. B. Yeats, J. M. Synge, Seán O'Casey and Lady Gregory, with their launch of the Abbey Theatre. By 1901 only approximately 641,000 people spoke Irish with only just 20,953 of those speakers being monolingual Irish speakers; how many had emigrated is unknown, but it is probably safe to say that a larger number of speakers lived elsewhere This change in demographics can be attributed to the Great Famine as well as the increasing social pressure to speak English. Even though the Abbey Theatre playwrights wrote in English (and indeed some disliked Irish) the Irish language affected them, as it did all Irish English speakers. The version of English spoken in Ireland, known as Hiberno-English bears similarities in some grammatical idioms with Irish. Writers who have used Hiberno-English include J.M. Synge, Yeats, George Bernard Shaw, Oscar Wilde and more recently in the writings of Seamus Heaney, Paul Durcan, and Dermot Bolger. This national cultural revival of the late 19th century and early 20th century matched the growing Irish radicalism in Irish politics. Many of those, such as Pearse, de Valera, W. T. Cosgrave (Liam Mac Cosguir) and Ernest Blythe (Earnán de Blaghd), who fought to achieve Irish independence and came to govern the independent Irish Free State, first became politically aware through Conradh na Gaeilge. Douglas Hyde had mentioned the necessity of "de-anglicizing" Ireland, as a cultural goal that was not overtly political. Hyde resigned from its presidency in 1915 in protest when the movement voted to affiliate with the separatist cause; it had been infiltrated by members of the secretive Irish Republican Brotherhood, and had changed from being a purely cultural group to one with radical nationalist aims. A Church of Ireland campaign to promote worship and religion in Irish was started in 1914 with the founding of Cumann Gaelach na hEaglaise (the Irish Guild of the Church). The Roman Catholic Church also replaced its liturgies in Latin with Irish and English following the Second Vatican Council in the 1960s, and its first Bible was published in 1981. The hit song Theme from Harry's Game by County Donegal music group Clannad, became the first song to appear on Britain's Top of the Pops with Irish lyrics in 1982. It has been estimated that there were around 800,000 monoglot