Mike Duncan launched his first history podcast, “The History of Rome,” in 2007 when podcasting was relatively new but surging as a new medium. It is now a pillar in the history podcasting community. In 2013, he started his second podcast, “Revolutions”―undeniably a second pillar. His in-depth research, required for creating such successful podcasts, has lent him the ability to successfully enter into another, much older, medium: books. Duncan’s second book, “Hero of Two Worlds: The Marquis de Lafayette in the Age of Revolution,” is a fine addition to the massive collection of American Revolution scholarship. In my opinion, it is a necessary addition. The Marquis de Lafayette is a recognizable figure for Americans. He was the French nobleman and military officer who came to aid the colonists in their fight against Britain during the American Revolution. Aside from his arrival, bravery in battle, and his close relationship to George …