It depends on the town Level (III for Rome) and on the military structures of the town. The information only related to the city : Your own culture is always displayed first with the other 2 other predominant ones after.

The Culture of the Province which is shared between all the cities regardless of the owners.Happiness ranges from -100 to +100 and affects the wealth bonus of your cities (from -40% at -100 to +20% at +100). It shows the current level of happiness (-2) and how it will change on the next tick (each 3 min) (-2.4). The Happiness which is shared between the towns owned by Rome only and in the province of Italia only.The information related to all the other towns of the Province (of Italia in our example):

Note that you may open/close it automatically with the Escape Key. When clicking on a Town or City, this panel opens.