He learned French, German, Spanish, Welsh, and Russian, and translated works from several Continental authors.
[1] Piaras Béaslaí said of Ó Rinn:[6] He did not write many original works, but the integrity of his critical opinion was unequalled; unswayed by consensus, applying his own reflection, examination, and judgment to every question relating to promoting Irish or to literature in Irish.
Art Ó Maolfhábhail noted his influence in writing about the modern urban world, including coining many new terms.
[7] Although Ruth Sherry says Ó Rinn's translation of "The Soldiers' Song" was first published in An tÓglach (the magazine of the Irish Defence Forces) on 3 November 1923,[3] an almost identical text was printed in the Freeman's Journal on 3 April 1923, under Ó Rinn's pen name "Coinneach".
[8] Other translations had already been made into literary Classical Irish, whereas Ó Rinn favoured the living vernacular spoken in Gaeltacht areas.