After some time, Meldercreutz bought his partners’ holdings, but he soon realised that operations were not easy to sustain. It was extremely difficult to find labour and to organise the transport of ore from Gällivare. Meldercreutz then requested that the king allow him to cultivate the wilderness landscape between the Rivers Luleå and Kalix. The state gave permission and Melderstein had a cultivation area 200 kilometres long and about 120 kilometres wide, generally called “the Duchy of Melderstein”. It was bigger than many of the kingdoms in Europe at the time. Settlers were offered land and a house to live in if they carried out tasks for Melderstein Works. Settlers arrived and Meldercreutz played an important role in the settlement of Norrbotten. In all, no less than 67 settlers moved there.

Meldercreutz was an ambitious businessman, who made his mark on the area around Melderstein. He built sawmills and a rifle factory in Melderstein, a hardware forge in Niemisel, a mill in Prästholm, and the Strömsund shipyard and brick works. With the help of farmers from Råneå, a blast furnace was built at Hasaforsen Rapids. In 1751, Meldercreutz became a Professor of Mathematics at Uppsala University and in 1739 he was made a member of the Royal Swedish Academy of Sciences. Alongside his intellectual commitments, he continued to run Melderstein until his death in 1785.

The Meldercreutz empire was bought by Jean Bedoire, who renovated the works and ran it until 1799, when a nobleman who is still renowned in Norrbotten – Samuel Gustaf Hermelin – bought the entire industrial complex. Like Meldercreutz, Hermelin had grand visions of developing and cultivating Norrbotten to the benefit of the entire country. Hermelin experienced severe economic difficulties with Melderstein and the other works owing to war, poor harvests, fires and shipwrecks. His time as the works owner ended in bankruptcy in 1812.