 Complete the following phrase:  Eighteen months later Stoecker was returned to the significantly expanded party central committee at that years party congress, held at Leipzig during JanuaryFebruary 1923. He was also given an important regional position as senior Polleiter loosely, head of policy for the Communist Partys region west, which comprised approximately the area covered since 1947 by North Rhine-Westphalia. According to at least one source he had effectively been filling an equivalent role on a less formal basis since 1921. The party had its regional headquarters at Cologne. During 1923 he was much involved in preparation for the 