Siege of the Unfinished Keep. Epic of Hornblood Castle, #1

A castle under construction, a nation under attack.Sam Freeman's been running from a life he's tried to escape. Now he's found a place, or at least he thinks he does, where he can be at peace. Creating, crafting, building. The pressures of the castle are starting to get to him, and he finds unexpected problems created by those who should be helping him. Hornblood Castle, nestled at the divergence of two rivers at the tip of Chathem, is intended to be a bastion for the kingdom, but the war-friendly Belmarch neighbors wouldn't look kindly on such an obstacle being put in their path.
When the Belmarch raiders arrive Sam finds his temporary paradise thrust into chaos. Will he be forced to fight, or is there another way to defeat the invaders without bloodshed?