This inquiry collated Irish and English literacy evolution in children attending diverse school types, evaluating word reading, decoding and vocabulary at three time points (second, third and fourth year of schooling). Children attending Irish-medium schools and a school in an Irish-speaking (Gaeltacht) community achieved considerably better than children attending an English-medium school on the Irish tasks. Discrepancies between Irish reading first (IRF) and English reading first (ERF) Irish medium school children were obvious only at the first time point, with IRF children displaying an early decoding benefit. Discrepancies between the school groups on the English tasks were mostly settled by the fourth schooling year. Collating the Irish-medium groups on English reading, the Gaeltacht group at first lagged behind the others, but there was no dissimilarity by the fourth schooling year. These findings propose that the language in which reading is formally initiated is not crucial for later reading achievement. Also, teaching through Irish was linked with Irish language benefits, without damage to English reading skill as measured here.