Episodes of Edge of History open with the same invitation. The Centurion, who calls himself its storyteller, welcomes the listener to a digital campfire and explains why he tells these stories at all: to keep the candles of underrated and underappreciated people and events lit. Sometimes that means celebrating heroism. Sometimes it means mourning what was lost. Always, as he puts it, it means learning something. The episodes here are chapters of a numbered series on American involvement in the Vietnam War. Titles run in sequence, among them 'Vietnam War: Origins (Part 2)', 'Vietnam War: Run to the Jungle (Part 4)' and 'Vietnam War: Marines (Part 6)'. He insists that order matters and more than once sends newcomers back to earlier parts for the backstory. He calls the war a humbling moment for what he terms 'our empire', and while he acknowledges the many movies made about it, he maintains that much about it is still not widely understood. The series stands out for where it spends its time. It takes the other side's reasoning seriously. In one stretch he imagines himself as a young man working fourteen-hour days in a rice paddy, to show why the pitch of a working-class revolution landed with colonized people. Elsewhere he describes Stalin's purges and the paranoia they bred, noting that those crimes were less visible abroad than to the victims inside the Soviet Union. He argues that Americans failed again and again to grasp North Vietnamese resolve, a belief in victory at whatever cost. The detail at ground level is just as deliberate. He explains how Green Berets trained and supplied Montagnard tribal fighters in the highlands, and where that French name comes from. He describes supply convoys ambushed on mined roads, and remote hilltop bases in the north, supplied by air, placed to intercept units crossing the demilitarized zone. Then he turns to people a civilian might never picture: mechanics checking oil and fluids on helicopters, crews keeping trucks and tanks working, and the workers handling fuel brought in by boat. The delivery is loose and conversational, closer to talk around a fire than a lecture. Closings return to gratitude and to the candle. He points listeners to the show's website for episode entries with pictures, source recommendations and books for further reading, and says literature is his other great passion.