Frederick Engels planned a full history of Ireland, but only wrote one chapter in the end. It seems quite a good summary of prehistory up to just before the English conquest and has many interesting points. See http://www.marxists.org/archive/marx/works/1870/history-ireland/ch02.htm

(chapter one was an article on the topography rather than the history of Ireland)

Bhal, bhí sé pósta ar Éireannach. B'fhéidir gur scríobh sise é.

Agus tháinig sé i dtír ar sclábhaithe d'oibrithe Éireanncha chomh maith! Thuig sé an córás on taobh istigh.

Sea, is ioróineach an scéal ag an Engelsach: Toice mór na reabhlóide tionscalta - monarchana i Manchuin aige - agus cúltacaí mór na reabhlóide sóisialta - choinnigh sé airgead le Cearl