The earliest surviving charter is one granted by King William the Lion about 1179. From its wording we can assume that Aberdeen was already a Royal Burgh and a trading community of some importance. King William paid many visits to Aberdeen, at a time when the Royal Court was not based in any one place.
It is really in the 12th century that Aberdeen, as we would begin to understand it, began to develop. It was an extremely important and flourishing trading port. By the end of the 12th century it had many of the hall marks of its future success: a castle, a new larger and impressive stone church st nicholas and a mint at the site of Atheneaum Bar. It is possible that the mint predated the reign of William I (possibly dating from the reign of David I). Nevertheless Aberdeen remained a centre of coin production in Scotland for sometime.
By the end of the 13th century Aberdeen had developed into a larger and more prosperous Royal Burgh. By the 1290s there were three orders of friars established in the town: the Red Friars (Trinitarians); the Black Friars (Dominicans) and the White Friars (Carmelites).
Archaeological evidence covering this period shows a prospering and busy town. Many of the goods enjoyed by wealthy Aberdonians were luxury goods imported from overseas, including fine pottery, clothing, spices and food. But with a growing town would also come the problems of overcrowding and disease.
Further charters were issued to Aberdeen in the 13th century. One dated between 1187 and 1203 freed Aberdonian merchants from tolls due on their goods throughout Scotland. Between1214 and 1222 Alexander II granted Aberdeen’s merchants the right to hold a weekly market, the rights to establish a merchant guild and a virtual monopoly of trade within the burgh and to a more limited extent in the sheriffdom. In 1273 Alexander III granted Aberdeen the right to hold an annual fair lasting for two weeks.By the end of the 13th century Aberdeen had a more complex and developed legal framework to allow for its trade to flourish and grow.