At this period , the wars of the Low Countries consisted almost entirely of sieges .
Spinola made himself famous by the number of places he took in spite of the efforts of Maurice of Nassau to defend them , including the heavily fortified Groenlo .
At this period , the wars of the Low Countries consisted almost entirely of sieges , and Spinola made himself famous by the number of places he took in spite of the efforts of Maurice of Nassau to defend them , including the heavily fortified Groenlo .