After Power Rangers S.P.D. (2005) and Power Rangers Mystic Force (2006), this is the third PR series to be dubbed in Japanese since Saban got the ownership of the Power Rangers franchise back. And like in the case of the Mystic Force dub, regular voice actors are used instead of the original Japanese actors.
The Red Samurai Ranger was going to be a Japanese-American young man named Mark Ozawa, descendent of a long line of samurai who fought against the Ashura Clan. His main rival would be a young man named Keiji Ayakawa, who would be revealed early on to be a descendent of Master Xandred, who in this version was defeated and petrified as a statue. Xandred would return, however, serving as the show's main villain. Keiji, jealous of Mark's samurai legacy, would readily join the Ashura Clan, as well as have the ability to transform into a demon (this would be Juzo's counterpart). The other four Rangers would hail from different countries, such as Austria, Nigeria, the UK, and Mexico.
Production on the show was out rushed in 6 months instead of the usual year due to the timing of Saban buying the franchise back and trying to get it out at the usual premiere time of early the next year. It tends to show in that most of the early episodes are just recycled Shinkenger plots.
The Ashura Clan originally operated from the Dread Castle, a demonic version of the Osaka Castle in Japan. The Moogers were originally called "Marauders," and Akumaro/Serrator would originally be a mystic who betrayed the Red Ranger's family, resurrected by Octoroo (here named "Octomancer") as a demon.
A surprising amount of research into actual samurai went into the show, to the point some people have assumed the writers didn't do their homework due to how obscure certain elements are. For example, the "ninja mask" that appears before the Ranger's helmets appear were actually worn by real samurai to help hold their helmets in place, and the face in the belt of Shogun Mode is based off actual belt buckles worn by certain noble samurai.