Kerby A. Miller, Arnold Schrier, Bruce D. Boling, David N. Doyle (2003). Irish immigrants in the land of Canaan: letters and memoirs from colonial and revolutionary America, 1675-1815. Oxford University Press US. http://books.google.com/books?id=bq79_YZ8ViIChttp://books.google.com/books?id=bq79_YZ8ViIC
Walter Lee Sheppard (1938, 1974) and Kerby Miller et al. (2003) cite a letter sent from Ireland in 1700 which mentions "Johnathan Waln" or "Jonathan Walen": "cosen david and his Cosen Jonathan walen and his good wife and Children and all ye rest of our relations and frinds there yt went alonge with you."
Kerby et al. (p13-23) gives a history of the Irish Baptists, explaining how English Baptists and Quakers settled in Ireland on land confiscated from Catholics after the Cromwellian conquest, 1649-50. Jonathan Walling (or Walen) was likely the son of one of these adventurers. One possibility is Patient Wallin, of London, who appears in a list of adventurers investing £100 in the settlement (John P. Prendergast, The Cromwellian Settlement of Ireland, 2d ed., Dublin, 1870, p431 http://books.google.com/books?id=RmoBAAAAQAAJhttp://books.google.com/books?id=RmoBAAAAQAAJ ).