Both Octavia, the sister of Augustus, and Livia, his wife, are usually shown with a peculiar hairstyle, called a nodus, which Octavia is said to have invented. The hair was tightly swept back into a bun with the bangs curled in a tight roll above the forehead. This was supposed to represent feminine modesty, purity, and ideal Roman womanhood. This style was soon copied by Roman women of all classes. My source postulates that this severe hairstyle was adopted in part as a direct difference to the ornate hairstyles of Cleopatra and other Eastern queens - a show of opposition as well as a show of national pride.


source: I Claudia: Women in Ancient Rome. Kleiner and Matheson, editors, Yale University Art Gallery, 1996.