Complex sentence: Thereafter, Noricum was called a province, although it was not organized as such and remained a kingdom with the title of "regnum Noricum", yet under the control of an imperial procurator.
Split into simpler sentences: Thereafter, Noricum was called a province, although it was not organized as such. It remained a kingdom with the title "regnum Noricum" and was under the control of an imperial procurator.