[3][4] Although the German Democratic Republic had been formally founded only in 1949, the basis for a return to one-party government had been established in April 1946, with the contentious merger of the old Communist Party with the Moderate-left SPD.
[3] Nationally, Steinberg became a deputy president of the CDU in December 1989, a month after the breach of the Berlin Wall had set in motion a series of events which would lead to reunification in October 1990.
After the 1990 election he served from April 1990 as Minister for Protection of the Environment and Nature, for Reactor Safety and for Energy under Lothar de Maizière.
His critical responsibilities included decommissioning principal sources of pollution in the old East German chemicals industry and the closure of the Greifswald Nuclear Power Plant.
In October 1990, he briefly served as the interim head of government of the newly re-established state of Saxony-Anhalt until the election of Minister-President Gerd Gies.
Soon after this he became Research Director with Preussag AG, and took on a project to develop a technology or system to reduce the high level of CO2 emitted by the company.
[3] He sought and found support both in the private sector and from the regional government [de] of Saxony-Anhalt, which invited him to establish his business in Klötze, some 20 km to the north-east of Wolfsburg.