settled and the city was now expanding on the ridges surrounding the city. Stockholm had no private palaces at this time and the only larger buildings were the castle, the church, and the former Greyfriars monastery on Riddarholmen. The surrounding ridges, unable to boast a single timber framed building, were mostly used for activities that either required a lot of space, produced odours, or could cause fire. Even though some burghers had secondary residences outside the city, the population living on the ridges, perhaps a quarter of the city's population, were mostly poor, including the royal personnel occupying the ridges north of the city. Great Power era Following the Thirty Years' War (1618–1648), Sweden was determined never to repeat the embarrassment experienced following the death of Gustavus II Adolphus (1594–1632) when Stockholm, still medieval in character, caused hesitation on whether to invite foreign statesmen for fear the lamentable appearance might undermine the nation's authority. Therefore, Stockholm saw many ambitious city plans during the era, of which those for the ridges surrounding today's old town still stands. In accordance to the mercantilism of the era, trade and industry was concentrated to cities where it was easier to control, and Stockholm was of central importance. In a letter in 1636, Chancellor Axel Oxenstierna (1583–1654) wrote that evolving the Swedish capital was a prerequisite for the nation's power and strength and that this would bring all the other cities on their feet. Increased state intervention on city level was not unique to Sweden at this time, but it was probably more prominent in the case of Stockholm than anywhere else in Europe. To this end, the government of the city was reformed and the former volunteered magistrates gradually replaced by professionals with a theoretical education. Population and city plans The process of reshaping Stockholm was initiated by a major fire in 1625 which destroyed the south-western part of today's old town. As a result, two new boulevard-like streets were created — Stora Nygatan and Lilla Nygatan — and along the eastern waterfront the medieval wall was replaced by a row of prestigious palaces — Skeppsbron. For the ridges surrounding the city – Norrmalm, Östermalm, Kungsholmen, and Södermalm – new city plans were worked out to create wide and straight artery streets. The project was implemented so thoroughly, in several parts of the city no traces exist of the previous medieval structures. Many of