● Sonic by Mary Garnet
There is another story about the Sonic The Hedgehog concept that could inspired Sega to create his game character.
At the 40's, dating back to World War 2, there was a popular writer of children's books called Mary Garnet and her husband was a test pilot for the United States Air Force. Her husband had an operation going on, which he named Project "Blue Gale." The purpose was build the first plane that could break the sound barrier. Mary always called her husband "hedgehog", since when he took his flight helmet off, his hair appeared to be all spiky, resembling the quills on a hedgehog's back. This name stuck and it inspired Mary to decorate his flight jacket with a blue hedgehog mascot. Their daughter Sherry was raised listening to the Mary's stories about a blue hedgehog named Sonic, the hero who would always save the world and protect innocent people and small animals from evil men.
On October 14th, 1947, General Charles Elwood Yeager (AKA Chuck Yeager) became the first man to break the sound barrier and from that day on he earned the dub The Fastest Man Alive. Earlier that same day, another pilot named Hedgehog had set out to break the record himself. He came close, but his plane began to vibrate and eventually exploded into a fireball.
Nobody remembers the name of the brave pilot, but veterans of the airbase still remember the emblem of Sonic the blue hedgehog. Whether or not the Mary Garnet story is true remains to be seen. But shades of it are visible all over the Sonic franchise.
In the old SatAM Sonic the Hedgehog cartoon, the lyrics of the opening theme referred to Sonic as The Fastest Thing Alive, similar to Chuck Yeager's dub, The Fastest Man Alive. Plus, Sonic's uncle in the series is named Chuck. That name was also given to Chris' Uncle in the recent series, Sonic X. But most importantly, the story was commented in 1991 by Sonic Team in a japanese magazine, and was told in a pamphlet that accompanied the Sonic Adventure 2 Special 10th anniversary gift pack.

● Sonic is reference to everyone
Whatever it may was the references in the life of Yuji Naka and Naoto Ohshima to create Sonic The Hedgehog, it worked very well. This hedgehog not only represents Sega and took the lead in a market once dominated by Nintendo, but influenced all the videogames industry too. Almost all the platform/adventure game characters created after Sonic release had his influence in a way or another.

Sparkster is one of these game characters because his spin attack resembles to Sonic's, and he also turns yellow and more powerful when he finds the 7 hidden swords. Havoc have some resemblance to Sonic's design and also runs faster picking up a shoes item. Aero The Acrobat, Bubsy, Ray Man, Zool, Bug!, Gex, and even more. All of them have something from Sonic in their concept design or in their own gameplay. Sonic The Hedgehog has become eternal and his legacy will still influences lots of characters.