Dieselpunk is a genre similar to steampunk that combines the Tier 2 Industrial technology and aesthetics of the diesel-based technology of the interwar period of the 1930s and 1940s with retro-futuristic technology and postmodern sensibilities.
Dieselpunk fashion is, in a lot of ways, similar to Steampunk fashion, but with a darker color palette to choose from. Popular items within Dieselpunk circles include waistcoats, arm covers, hosiery, bomber jackets, zoot suits, wristwatches, goggles, overalls; basically, anything that would've been worn during the interwar period that Dieselpunk is designed to emulate.
Fiction and Literature
Dieselpunk literature takes place during the 1930s and 1940s. The aesthetic is primarily utilized in books, like David Bishop's Fiends of the Eastern Front, Kevin Cooney's Tales of the First Occult War, Larry Correia's Hard Magic: Book 1 of the Grimnoir Chronicles and Richard Kadrey's The Grand Dark, but there are plenty of movies that utilize the Dieselpunk aesthtetic, such as Brazil, Sky Captain and the World of Tomorrow, The Rocketeer, Iron Sky (which, hilariously, is also about Nazis, so there's one for those Fashwave people), and even Captain America: The First Avenger could be considered Dieselpunk cinema. Dieselpunk is even adopted into video games like Fallout (which can crossover into Raypunk at times), Bioshock (which is probably more Decopunk), Final Fantasy VII, and Wolfenstein: The New Order.
Dieselpunk music tends to draw heavily from the era, so there is a lot of jazz, blues, ragtime, cabaret, big band, swing, and bluegrass from the time, but two modern genres have grown to evoke the Dieselpunk aesthetic: Electro Swing and Neo-Swing. Electro Swing is a combination of Electronica music with swing music made popular by groups such as Caravan Palace, Good Co, and Tape Five. Neo-Swing, however, were bands that were designed to be throwbacks to the era of Big Band that started becoming really popular in the late 90's thanks to acts like the Cherry Poppin' Daddies, Lee Press-on and the Nails, Squirrel Nut Zippers, the Brian Setzer Orchestra, Big Rude Jake, and RPM Orchestra. However, thanks to Dieselpunk, these bands have enjoyed some continued success even after fading away from the mainstream eye.