The episode's title refers to a historic Scottish signal used by a chieftain to call his men to war. Jamie is forced into this role by , who demands that Jamie raise a militia to hunt down the "Regulators"—a group of rebels led by Jamie's own godfather, Murtagh Fitzgibbons .
When he lights the Fiery Cross, he isn't just calling his men to arms; he is claiming a future for his family while acknowledging the blood that will inevitably be spilled to keep it. The Deep Conflict