Sonic Team explains Eggman's name change

At this point, we all know about Sonic and his arch-enemy, Dr. Eggman. However, younger fans might be surprised that Dr. Eggman used to be called "Dr. Ivo Robotnik" back when the first few Sonic the Hedgehog titles were released in the US, in the early 90's. It wasn't until 1999's Sonic Adventure that the developers decided to revert his name back to Dr. Eggman, as seen in the clip below (remade via Steam Film Maker)

Sonic Team's Takashi Iizuka finally explained why the name change happened. 

Speaking with Game Informer,  he explained that when the original game was localized, the western team, "without consulting" with the team overseas, changed it to "Ivo Robotnik." Over time, after Sonic gained popularity, Sega wanted to unify the names, which was an effort spearheaded by Iizuka. So, in Sonic Adventure, they decided to combine the two names and make "Dr. Ivo "Eggman" Robotnik" the official name for the mad doctor. You can read the full interview on GameInformer's website..