The Coat of Arms is used as a symbol to identify people, families, clans and tribes. They are used today to separate cities (for example, the City of London and the City of Westminster - pretty much the same place [I use this term loosely!], but different coat of arms)
The Birmingham Coat of Arms was first used in 1838 when Birmingham was a borough. It has changed several times, with parts added and colours changed. It is based on the de Bermingham family armorial bearings, and the supporters (the female and male figures on each side) were added in 1899 when Birmingham became a City. In 1976 a new Coat of Arms was adopted, this time incorporating Sutton Coldfield (the Tudor Rose in the crown which commemorates Henry VIII granting a charter to Sutton Coldfield in 1528).
The colours and patterns of the main shield are taken from the City Flag, which can be seen flying from the Council House daily. Parts of the flag date back to 1325. The ermine cross which goes across the shield represents Edgbaston and Sutton Coldfield, and the Bishops mitre in the centre represents John Vesey, Bishop of Exeter, who was born in Sutton and procured the charter from Henry VIII, amongst other things.
Quite a lot of history in our Coat of Arms! You can see it in most places around the City - it features on buildings, road signs and used to be on the buses and rubbish trucks!
You can read more about it here, as well as by following the links in the text.