This thesis focuses on power structures in the Mälaren basin during the Iron Age, and how these structures change over time. In the veiwpoint of the author, constructing large mounds vas an important way for the elite in the Mälaren basin to distinguish themelves from other groups in the region during the relevant period. By studying how the mounds differ in size an contents in relation to the norm, at least two different social strata can be discernd. The lower stratum vas similar to warriors than head of power, and vice versa. The burial mounds from The Late Iron Age are almost always located in burial-grounds which belong to villages and farms, which often extend back to the transition between Roman Iron Age and Migration period. The analysis also reveals that large mounds were built mainly in the Vendel period (AD 550-700) and the late Viking Age (tenth century). To find out how the elite used the large mounds in their social strategies, the author conducts a landscape-archaeological analysis. The analysis shows that large mound often are situated in important junctions in the landscapes, some served at meeting places for the Ting, but they seldom coincides with cult places, insted the cult places are often situated on the perifery of the settlement complexes with large mounds. Finally the author sets the results of analysis in a culture-historical context. The discussion focuses on when and why large mounds were built in the Mälaren basin during the Iron Age.