[2] After receiving his Ph.D., he spent a year studying in Dublin, Ireland, then returned to the United States in 1910 to take up a position as an instructor at Harvard.
[4] Cross's final work, the Motif-Index of Early Irish Literature, whose compilation he had begun more than five decades earlier at the inspiration of Fred N. Robinson, was published post-humously as part of Indiana University Bloomington's Folklore Series in 1952.
Stith Thompson, who visited him in late 1951, reported that he worked literally until the day he died reading the galley proofs in order to complete the corrections.
[9] However, William Sayers would half a century later criticise it as being limited by its "original conceptual categories, where such modern notions as ideology, gender, physical aberrance, the abject and the like are absent".
[2] He had one younger brother, Hardy Cross, who would go on to achieve fame in the field of structural engineering for his development of the moment distribution method.
[2] Late in life, he suffered a heart attack, and his poor health kept him from being able to climb stairs, but he still continued his work on his Motif-Index.