Natalie Wynn (Contrapoints) mentioned The Decline of the West by Oswald Spengler 1 times

But in its contemporary sense, the idea of "Western culture" didn't really exist until the imperialist era of the late 19th and early 20th centuries when it was popularized in part by Oswald Spengler's 1918 book, 'The Decline of the West', an important influence on Nazi ideology.

— Natalie Wynn (Contrapoints)