In 1870 came the Franco-Prussian war and Nietzsche decided to go to the front. Despite his hatred of all the cant of cheap patriotism and his pious thankfulness that he was a Pole and not a German, he was at bottom a good citizen and perfectly willing to suffer and bleed for his country. But unluckily he had taken out Swiss naturalization papers in order to be able to accept his appointment at Basel, and so, as the subject of a neutral state, he had to go to the war, not as a warrior, but as a hospital steward. Even as it was, Nietzsche came near giving his life to Germany. He was not strong physically--he had suffered from severe headaches as far back as 1862--and his hard work at Basel had further weakened him. On the battlefields of France he grew ill. Diphtheria and what seems to have been cholera morbus attacked him and when he finally reached home again he was a neurasthenic wreck. Ever thereafter his life was one long struggle against disease. He suffered from migraine, that most terrible disease of the nerves, and chronic catarrh of the stomach made him a dyspeptic. Unable to eat or sleep, he resorted to narcotics, and according to his sister, he continued their use throughout his life. "He wanted to get well quickly," she says, "and so took double doses." Nietzsche, indeed, was a slave to drugs, and more than once in after life, long before insanity finally ended his career, he gave evidence of it. Despite his illness he insisted upon resuming work, but during the following winter he was obliged to take a vacation in Italy. Meanwhile he had delivered lectures to his classes on the Greek drama and two of these he revised and published, in 1872, as his first book, "_Die Geburt der Tragödie_" ("The Birth of Tragedy"). Engelmann, the great Leipsic publisher, declined it, but Fritsch, of the same city, put it into type.[5] This book greatly pleased his friends, but the old-line philologists of the time thought it wild and extravagant, and it almost cost Nietzsche his professorship. Students were advised to keep away from him, and during the winter of 1872-3, it is said, he had no pupils at all.