Eoin was born in Wexford, a picturesque coastal town in the southeast corner of Ireland. Attending the primary school where his father taught, Eoin first developed his interest in writing and began his life long habit of writing his own stories complete with illustrations.

He qualified as a primary teacher in 1986. He began teaching in a local primary school by day but continued to write at night. Eoin rapidly became involved in the local amateur drama group starring in, directing and later writing many award winning productions. His monster best seller Artemis Fowl was published in 2001.