In the course of a sojourn to Europe, Biddle sailed to Greece, then a part of the Ottoman Empire. Half of the journal he kept on the trip has only recently been discovered, and the other half is known to only a few people because it is still in private hands. Taken together, these two journals (plus the four extant letters that Biddle wrote to his family in Philadelphia) are a mine of information about the formative influences on his career, about the politics and personalities of Napoleon's Europe, about the condition of Greece and its ancient monuments under the Turkocratia, and even about the American naval war against the Barbary pirates. Despite being written by a twenty-year-old, these journals are remarkable for their literary quality and their general liveliness. Perhaps because they were not written to be published, they have a freshness and honesty lacking in more formal works of travel.