Complex sentence: He proceeded with cautious reforms such as the establishment of fiscal and military ministries and the introduction of a national customs tariff, which soon had to be abandoned because of the opposition from Frederick II the Great of Prussia.
Split into simpler sentences: He proceeded with cautious reforms such as the establishment of fiscal and military ministries and the introduction of a national customs tariff. The customs tariff soon had to be abandoned because of the opposition from Frederick II the Great of Prussia.