Gobineau encouraged Eulenburg to promote his theory of an Aryan master-race, telling him: "In this way you will help many people understand things sooner."[135] Later, Eulenburg was to complain all of his letters to Gobineau had to be destroyed because "They contain too much of an intimately personal nature".[136] During his time in Sweden, Gobineau became obsessed with the Vikings and became intent on proving he was descended from the Norse.[137] His time in Stockholm was a very productive period from a literary viewpoint. He wrote Les Pléiades ("The Pleiades"), Les Nouvelles Asiatiques ("The New Asians"), La Renaissance, most of Histoire de Ottar Jarl, pirate norvégien conquérant du pays de Bray en Normandie et de sa descendance ("History of Ottar Jarl, Norwegian Pirate and Conqueror of Normandy and his Descendants") and completed the first half of his epic poem Amadis while serving as minister to Sweden.[137]