Ancient Roman cuisine  Ancient Roman cuisine changed greatly over the duration of the civilization's existence. Dietary habits were affected by the political changes from kingdom to republic to empire, and the empire's enormous expansion, which exposed Romans to many new provincial culinary habits and cooking methods. In the beginning, dietary differences between Roman social classes were not great, but disparities developed with the empire's growth. Traditionally, a breakfast called "ientaculum" was served at dawn. At mid-day to early afternoon, Romans ate "cena", the main meal of the day, and at nightfall a light supper called "vesperna". With the increased importation of foreign foods, the "cena" grew larger in size and included a wider range of foods. Thus, it gradually shifted to the evening, while the "vesperna" was abandoned completely over the course of the years. The mid-day meal "prandium" became a light meal to hold one over until "cena". Among the lower classes of the Roman society, these changes were less pronounced as the traditional routines corresponded closely to the daily rhythms of manual labour. However, among the upper classes, who normally did not engage in manual labour, it became customary to schedule all business obligations in the morning. After the "prandium", the last responsibilities would be discharged, and a visit would be made to the baths. Around 2 p.m., the " cena" would begin. This meal could last until late in the night, especially if guests were invited, and would often be followed by "comissatio", a round of alcoholic beverages (usually wine.) In the period of the kings and the early Republic, but also in later periods (for the working classes), the "cena" essentially consisted of a kind of porridge, the "puls". The simplest kind would be made from emmer, water, salt and fat. A more sophisticated variation was made with olive oil, and consumed with an accompaniment of assorted vegetables when available. The wealthy commonly ate their "puls" with eggs, cheese, and honey and it was also occasionally served with meat or fish. Over the course of the Republican period, the "Cena" developed into two courses: the main course and a dessert with fruit and seafood (e.g. molluscs, shrimp). By the end of the Republic, it was usual for the meal to be served in three parts: an appetiser ("gustatio"), main course ("primae mensae"), and dessert ("secundae mensae").