Burgess originally meant a freeman of a borough (England, Wales, Ireland) or burgh (Scotland). It later came to mean an elected or unelected official of a municipality, or the representative of a borough in the English House of Commons.
It was derived in Middle English and Middle Scots from the Old French word burgeis, simply meaning "an inhabitant of a town" (cf. burgeis or burges respectively). The Old French word burgeis is derived from bourg, meaning a market town or medieval village, itself derived from Late Latin burgus, meaning "fortress" or "wall". In effect, the reference was to the north-west European medieval and renaissance merchant class which tended to set up their storefronts along the outside of the city wall, where traffic through the gates was an advantage and safety in event of an attack was easily accessible. The right to seek shelter within a burg was known as the right of burgess.
The term was close in meaning to the Germanic term burgher, a formally defined class in medieval German cities (Middle Dutch burgher, Dutch burger and German Bürger). It is also linguistically close to the French term Bourgeois, which evolved from burgeis.
The original version of the well-known English folk song "Greensleeves" includes the following:
Thy purse and eke thy gay guilt knives,
thy pincase gallant to the eye:
No better wore the Burgesse wives,
and yet thou wouldst not love me.
This clearly implies that at the time when it was composed (late 16th to early 17th century) a burgess was proverbial as being able to provide his wife with beautiful and expensive clothes.