Glasgow was probably founded in the 6th century when St Mungo built a church at place called Glas Gu. (It means green place). A fishing settlement at the green place eventually grew into a small town. Glasgow was given a bishop in 1115, indicating it was a fairly important settlement by that time.
In the late Middle Ages Glasgow slowly grew more important. In 1410 the wooden bridge across the Clyde was replaced with a stone one. Glasgow did not have stone walls but it did have stone gates (the spaces between them were filled by houses). Then in 1491 the Bishop of Glasgow was granted the right to operate a public scales for weighing produce. It was called the Tron and it gave its name to the Trongate.
As a sign of its growing importance Glasgow in 1451 Glasgow was allowed to have a university . The Papal document that founded the university described Glasgow as a 'place of renown, where the air is mild and victuals are plentiful'. A grammar school was founded in Glasgow in 1460. Meanwhile in 1454 Glasgow was made a royal burgh. Then in 1492 Glasgow was given an archbishop.