He published the following works: Prynedig-aeth Neillduol neu Grist yn rhoi ei hun dros yr Eglwys, 1819?; Amddiffyniad yr Athrawiaeth Ysgrythyrol o Brynedigaeth Neillduol, 1820, a translation of J. Hurrion's book; Pedwar Cyflwr Dyn, 1821, a translation of Thomas Boston's work (the translation bears the name of J. Parry (1775-1846) (q.v.), but is believed to have been the work of Ieuan Glan Geirionydd); Hymnau i'w defnyddio yn Eglwys St. Martin, y Prydnawn Sabboth cyntaf o'r Flwyddyn; Casgliad o Salmau a Hymnau at wasanaeth y Lithwriaeth Gymraeg yn Nghaerlleon, 1829 (Geirionydd asserts that ‘Y Lithwriaeth Gymraeg’ meant ‘Welsh Lectureship,’ but in all probability it was intended to mean ‘Welsh Liturgy’); Y Seraph, sef casgliad o donau crefyddol ar amrywiol fesurau; Y Bibl Darluniadol, 1844-7.
Ieuan Glan Geirionydd assisted Rev. John Parry of Chester (see above) to edit the monthly Goleuad Gwynedd; in 1830 he sent a letter to the bishops asking for their patronage for a proposed Welsh periodical on the lines of the Saturday Magazine, and in 1833 Y Gwladgarwr appeared. Ieuan edited this for three years but, as he lost money on it, it passed into the ownership of Edward Parry of Chester. He won the chair at the S. Asaph eisteddfod, 1818, with his ‘Awdl ar farwolaeth y Dywysoges Charlotte’; at the Denbigh eisteddfod, 1828, with his ‘Awdl ar Wledd Belsassar’; and at the Denbigh eisteddfod, 1850, with his pryddest ‘Yr Adgyfodiad.’
Ieuan was the most versatile Welsh poet of the last century. Apart from the classical forms, he wrote lyrics in the modern manner, and hymns. He belonged to the liberal school of Gwallter Mechain which attacked the classical metres and began to write pryddestau and lyrics. His poems were influenced by the English ‘churchyard school’ — Gray, Robert Blair, and Edward Young — and his hymns by English hymn-writers like Watts.
David Gwenallt Jones, M.A., (1899-1968), Aberystwyth