The Precambrian of southern Sweden represents a gradual accretion of the Baltic Shield. The Svecofennian region in the east was stabilized by about 1750 Ma. In the west, an orogenic event between ca. 1600 and 1700 Ma added new continental crust to the shield, possibly also reworking a marginal segment of the Svecofennian. A continuous belt of granites and porphyries marks the boundary of the south-western orogen with the stable Svecofennian region. The subsequent development of southern Sweden was essentially ensialic, periods of granite intrusion and metamorphism interrupting anorogenic developments. In a final culmination of activity around 900–1100 Ma, southern Sweden played the role of a crustal segment marginal to the Grenvillian orogen.