I came across this fascinating site from Princeton University’s Graphic Arts blog.
They got a hold of Nast 1860 European passport. Before the Civil War and employment with Harper’s Weekly Nast and as the passport stamps and registry shows, traveled extensively in Europe.
“In 1859, Nast was hired by the New York Illustrated News but this passport was issued on 17 May 1860 so he could travel to Sicily representing The Illustrated London News and report on Giuseppe Garaibaldi’s military campaign to unify Italy. Mott notes that “Nast had not been paid by his employer, and had no money to make his Italian trip until Heenan, the American pugilist, lent him the necessary funds. Nast followed Garibaldi from Sicily to Naples, right through the battle of Volturno, October 1-2, and his articles and illustrations covering the war captured the American imagination.”