Marcus Aurelius wrote his 12 books, "To Himself," in Hellenistic Greek as a source for his own guidance and self-improvement. It is likely that large sections of the work were written in Sirmium, where he spent much time planning military campaigns from 170 to 180. Some of these were written while he was in Aquincum on campaign in Pannonia, as internal notes indicate that the first book was written while campaigning against the Quadi on the Granova River (modern Chron), and the second book was written in Carnuntum. It is unlikely that Marcus Aurelius ever intended for the writings to be published. The work has no official title, so "To Himself" is one of many titles often attributed to the collection. These writings take the form of excerpts varying in length from a single sentence to long paragraphs. The text was written according to the author's moods, resulting in a simple, austere style.