economy and transport in Brandenburg. In this capacity, he was, from June 1946 onwards, chairman of the newly established sequester commission in the province. 1946 was also the year of the forced merger of eastern KPD and eastern SPD into the Socialist Unity Party of Germany (SED), resulting in Rau's membership in the SED. Important 1946 events in Brandenburg were in November elections, which preceded an official status change from a province to a federal state in the following year. Afterwards, from 1946 until 1948, Rau was state parliament delegate and Minister for Economic Planning of Brandenburg.