Complex sentence: When King John sees the French surrender to Robin instead of himself, he senses a threat to his power, and reneges on his promise to sign the charter; in London, he declares Robin an outlaw, to be hunted throughout the kingdom.
Split into simpler sentences: When King John sees the French surrender to Robin instead of himself, he senses a threat to his power. In London John reneges on his promise to sign the charter, instead declaring Robin an outlaw to be hunted throughout the kingdom.