The original Normans were Viking raiders and invaders.  We went wherever we wanted and took what we wanted if someone did not want to trade us for it.  We even conquered northern France.  We conquered other regions as well, but after that most of our expansions were through well-placed marriages.  In the end, Norman blood flowed through the veins of every monarch in Europe and some beyond.  It made for interesting family dinners when relatives came calling.