Riddarfjärden
Riddarfjärden (, "The Knight Firth") is the easternmost bay of Lake Mälaren in central Stockholm. Stockholm was founded in 1252 on an island in the stream where Lake Mälaren (from the west) drains into the Baltic Sea (to the east); today the island is called Stadsholmen and constitutes Stockholm's Old Town.
Stockholm during the Swedish Empire
Erik Dahlberg, c. 1660–1680.
To this end, a reform in 1636 replaced the medieval city council with four committees ("kollegier"), each having a magistrate ("borgmästare") and three aldermen ("rådmän"), responsible for justice, trade, administration, and construction respectively. This reform was most likely triggered by the establishment of the Office of the Over-Governor of Stockholm ("överståthållarämbetet") in 1634, an office designed to be the government's tool in Stockholm and apparently conceived by Axel Oxenstierna himself. The first Over-Governor to be appointed was Claes Fleming (1592–1644, in office 1634–1644). 
Because the management of the city had been a spare time occupation beside regular business activities, appointment to the council had previously been based on experience of commerce. The government, wanting to render municipal management more efficient, was instead devoted to promote men with a theoretical education. Two of them were Anders Torstensson, a man who had a profound impact on the development, and Nicodemus Tessin the Elder, the first City Architect. Furthermore, to increase construction quality the qualifications to admission to the mason's guild, members of which were the de facto architects at this time, were straightened up.