German nationalism and 'Aryanism' began in the late 19th century, under Wilhelm I and became widespread under Wilhelm II. It was a deliberate program to build patriotism and nationalism in the new German Federation forming then; 'Germany is a much newer country than many assume it is, and so is Italy, but in any case such luminaries as Max Weber was a member of a 'nationalist' group; the 'Master Race' idea came along near the same time as an off-shoot of the German nationalism agenda.
The American eugenicist Charles Davenport was the major influence,at least on Nazi ideology. You can find many of his articles in old 19th century Psychology magazines in the archives at HEARTH, the Cornell Library site for out of copyright books.
The American eugenicist Charles Davenport was the major influence,at least on Nazi ideology. You can find many of his articles in old 19th century Psychology magazines in the archives at HEARTH, the Cornell Library site for out of copyright books.