Complex sentence: Later, Gray, who was one of the wealthiest men in Virginia and owned tens of thousands of acres of land bet the Swann's Point property on game of cards and lost, and true to his word he transferred the property to the winner.
Split into simpler sentences: Later, Gray, who was one of the wealthiest men in Virginia and owned tens of thousands of acres of land bet the Swann's Point property on game of cards and lost. True to his word he transferred the property to the winner.