sentences:  Initially, Koszalin was the first post-war regional capital of Polish Western Pomerania, before the administration finally moved to Szczecin in February 1946, after which the region was named the Szczecin Voivodeship.In 1950 this voivodeship was divided into a truncated Szczecin Voivodeship and Koszalin Voivodeship.In years 1950-75 Koszalin was the capital of the enlarged Koszalin Voivodeship sometimes called Middle Pomerania due to becoming the fastest growing city in Poland.