I am aware that Noah Webster (1758--1843 AD) is responsible for the majority of the differences between British and American spelling (IE: "color" v "colour"). Over time, it seems, in his Speller textbook, he slowly phased out the British spellings for spellings he personally favored.
According to the Wikipedia page about Noah Webster:
Slowly, edition by edition, Webster changed the spelling of words, making them "Americanized". He chose s over c in words like defense, he changed the re to er in words like center, and he dropped one of the Ls in traveler. At first he kept the u in words like colour or favour but dropped it in later editions. He also changed "tongue" to "tung"—an innovation that never caught on.
My question is, did Noah Webster ever explicitly state why he made these changes, either in his books or private correspondences? Also, are there any records of him consulting others while making these decisions or did he act unilaterally?