There are 3 bands with the name Mugwumps. 1. A Japanese punk band The once-closed doors of the very domestic Japanese punk scene are being busted wide open with bands like the Mugwumps. True pop punk at its finest. Formed in 2004, the members are Hiroyuki Koike (Vocals/Guitar), Yoshitaka Shinmura (Vocals/Bass), and Kozo Kurosawa (Drums). Influenced by bands such as Descendents, All, Green Day, Dickies, The Muffs, but have thrown in their own elements to make their own sweet melodies 2. A pop/rock band from the 1960's.