For the Roman emperors, providing food for the people of Rome was a big deal (hence, Bread and Circuses, a line in a poem by the satirist Juvenal). Food for the Romans also carried a religious significance, with many festivals having dedicated feasting days. As the western world’s first global superpower, Rome had access to food and dishes from every corner of the empire. A Roman could look forward to such delights as wild boar, hare, snails and as a special treat – dormice. Garum, a paste made of fermented fish guts, was especially popular.
Inns, taverns and roadside stalls would all sell takeaway foods. These were mainly for the lower classes – food eaten while coming and going.
For the upper classes, the emphasis was on leisurely dining at home in pleasant surroundings. At sophisticated dinner parties, multiple courses were served while guests reclined and enjoyed the fruits of civilisation. Banquets could also be hosted by the Collegium (guilds, social clubs and civic/religious associations. Similar to the curry club at work).
Barley, however, was the main staple crop. Gladiators would consume it in vast quantities to help them bulk out for the arena and grow fat for plenty of padding. Hence their sobriquet, Hordearii or Barley Men.
There are some great examples from various eras here. Thanks to Jack Shannon for this article!