The American Revolution ended any political ties to British royalty. But it gave birth to American founding dynasties. Two generations later the leaders of two of these family dynasties--Mason and Adams--met on the diplomatic battlefield of this nation's only Civil War. One would emerge triumphant; both would die without public fanfare signaling end end to they families' national political prominence. Clashing Dynasties: Charles Francis Adams and James Murray Mason in the Fiery Cauldron of Civil War is the epic story of two grandson of two founders of the American Republic who followed two very different roads in life to arrive at the same critical crossroad of the Civil War. One was trying to preserve a unified American Republic and end slavery. The other was trying to destroy the American Republic and preserve slavery. Both men were burdened and buoyed by their family name, connections and traditions. Whether it is called the Civil War, The War Between the States, War of Northern Aggression, War for Southern Independence or any other designation, this internecine war touched off by the seceding southern states was the bloodiest existential threat to the United States. Diplomacy was an important, some argue critical, factor in the Civil War. Whether Great Britain and the European powers recognized or even aided the Confederacy was arguably the most important question of the day. Adams and Mason were at the center of this diplomatic struggle in London. Their missions conflicted, but their roles were identical--convince the British government to support their government. The United States teetered on the brink of war with Great Britain, as Adams and Mason fought for supremacy within Whitehall. One could argue that success or failure in the war rode on the shoulders of Adams and Mason.