Becoming a city has nothing to do with building a cathedral or a university or any similar institution. It is a status which is granted by the governing power of the time. Today this is Parliament; in the Middle Ages it was the king.

Over the years, Rochester has been granted many charters outlining municipal privileges. One of the most important was that allowed by Henry III in 1227. This was probably the occasion for the manufacture of the city seal now on display at the Guildhall Museum. This depicts Rochester Castle on one side, St Andrew on the other and would have been used to authenticate official documents.

The privileges granted in these charters would have included the right to levy duties and taxes. This was especially important for Rochester. The town quay would have been an ideal place to unload imported goods for distribution throughout north Kent.

In 1446 the city was given jurisdiction over the River Medway stretching all the way from Hawkswood out to Sheerness. Charters also provided for the election and appointment of city officials. It was in 1461 that Edward IV first granted Rochester the right to elect its own mayor.