A very unique connection to Ballykelly comes through the ancestry of the Noble Peace Prize winner for Literature, John Steinbeck (1902-1968), one of America’s best-known authors who wrote such classics as 'East of Eden', 'Of Mice and Men' and The Grapes of Wrath' for which he won the Pulitzer Prize. He came here in 1952 to trace his ancestors. Steinbeck's maternal grandfather was Samuel Hamilton who was born in Ballykelly in 1830 and baptized in the Presbyterian Church. The family farm (now gone) was at Mullkeeragh just off the Tully Road on the edge of the village. Samuel Hamilton emigrated to America during the famine years, he met and married Elizabeth Fagan in New York in 1849 and they moved to California and lived in the Salina Valley.
John Steinbeck and his wife Elaine visited Ballykelly on 18th August,1952 to discover where his ancestors had come from and to try and find any surviving members locally. At first they went to the Presbyterian church graveyard where his grandfather had been baptized. Eventually they discovered the Hamilton headstones in Tamlaghtfinlagan Parish Church and one marking Elizabeth (Minnie) Hamilton, who had passed away on February 11th, 1951, aged 84, two years before his visit. Minnie was the daughter of Samuel Hamilton's brother, William John Hamilton and Jane Ritchie. In his article ‘I go back to Ireland’ which was published in 1953 in Colliers Magazine, a photograph shows John Steinbeck crouching beside the two Hamilton headstones.