After Naoto Oshima, Yuji Naka, Hirokazu Yasuhara et al, made Sonic the Hedgehog, they were about to introduce to SEGA’s U.S. division, SEGA of America, Inc.
While at SEGA of America, the people there were very weary of Sonic’s design. Having taken cues of American culture but having an animal not common in America as the type of animal the character, a hedgehog, which was common Japan, as well as Europe, but not common in the US. Then SEGA of America went into full panic mode and they would more likely choose alternate designs to suit American tastes.
In order to make it suit audiences in America (as well as other Western nations), SEGA of America needed change the plotline, such as discarding real islands in the Pacific and Indian Oceans, such as Christmas Island and South Island and originally intended to be replaced with somewhere in America.
Also the Western plotlines say that Sonic was originally a brown hedgehog called “Sonny Hedgehog” that eventually became a blue hedgehog called Sonic.
However later this was replaced with a animal inhabited planet called “Mobius”, never used in Japan, but a world based on it was later used in modern Sonic games to this day, simply not having a name.
Dean Sitton, a SEGA of America help line employee wanted all the robot animals, which would become “badniks”, a term still used by Western Sonic fans to this day, to be renamed; such as Motora being renamed Motorbug in the Western release.
Also, Dr. Eggman was to renamed too, changing his name to Dr. Ivo Robotnik for the Western release, the most recognizable Western rename of a Sonic character. Ivo being pronounced like “evil” for an American person.
However these names along with later names like Floating Island, which was the Western name for Angel island and Nack the Weasel, the Western name for Fang the Sniper, continued to be used in the West until the release of Sonic Adventure which was released in the West in 1999, being released in Japan the previous year.