Complex sentence: The Spanish Stadtholder in the region Francisco Verdugo noted that Coevorden was crucial to Spanish rule in the northern Netherlands and was important for their stranglehold in Drenthe therefore he was committed to retaking it.
Split into simpler sentences: The Spanish Stadtholder in the region Francisco Verdugo noted that Coevorden was crucial to Spanish rule in the northern Netherlands. It was also important for the Spanish stranglehold in Drenthe therefore he was committed to retaking it.