Dear Mr. Cornwell, I’m currently reading (actually, listening to) The Last Kingdom, which I’m enjoying very much. I also loved your Warlord Series. My question is this. I notice that in these stories, battles frequently occurred through the confrontation of two “shield walls”. Two questions: (a) First, what are your primary sources that describe the shield wall, or is that something you inferred from the military technology (or lack thereof) of the time, and (b) do you know whether similar tactics were used at the same time in Francia by the Merovingian and Carolingian’s, or did their use of horsemen make the shield wall less relevant. Thanks! Michael Newman