Since its foundation the ICHS has encouraged and supported bibliographic activity related to finding, listing and making public published work in Irish history. Over time this work has been consolidated into, first, Writings on Irish History (1938-2004) and, since 2004, the online bibliography Irish History Online (IHO). IHO lists and indexes bibliographic information on books, pamphlets, articles from edited collections (including festschriften and conference proceedings) and from journals published in Ireland and internationally. It currently contains over 98,000 entries. In 2017 the website was upgraded with a new, enhanced search capability. It is free to end users.
IHO is professionally compiled by a team of voluntary editors and compilers and is hosted and managed by the Royal Irish Academy Library in Dublin.