A "merchant submarine" ends up commencing the only attack on the contiguous United States by the Central Powers of the First World War. The History Guy remembers SM U-156 and the Battle of Orleans. The History Guy uses media that are in the public domain. As photographs of actual events are sometimes not available, photographs of similar objects and events are used for illustration. Facebook: https://www.facebook.com/TheHistoryGuyYT/ Patreon: https://www.patreon.com/TheHistoryGuy The History Guy: Five Minutes of History is the place to find short snippets of forgotten history from five to fifteen minutes long. If you like history too, this is the channel for you. Subscribe for more forgotten history: https://www.youtube.com/channel/UC4sEmXUuWIFlxRIFBRV6VXQ?sub_confirmation=1. Awesome The History Guy merchandise is available at: https://teespring.com/stores/the-history-guy The episode is intended for educational purposes. All events are portrayed in historical context. #ushistory #thehistoryguy #wwi