Noah Webster has a lot to answer for. Born in Connecticut in 1758, he is most renowned for the dictionary, first published in 1806, that still bears his name. Yet his greatest influence on the world began earlier, as the man who taught America to spell. It's often assumed that the gulf between American and British spellings evolved like the traits of a single species distributed across two drifting continental plates: incrementally, ineffably, and in response to local conditions. In fact, a large part of it is attributable to the ideas of this evangelical Christian schoolmaster-turned-lexicographer, who believed that education was "useless without the Bible," and who saw spelling as the battleground for a righteous war against classical decadence: a national moral campaign against bad old-world habits like "ph" and "ou."
In 1783, Webster began marketing what later became The American Spelling Book. Part of a comprehensive attempt to remould American English along republican, Christian lines (it was published along with a grammar and a reader), it was a title that found great favour in post-revolutionary America. It went through no less than 385 editions in Webster's lifetime, and helped enshrine many of those differences that even today make writing "color" or "plow" a minor commemoration of his ambitions. Even republican America, however, lacked the will to enforce the full programme of godly reform Webster would have liked. Among many others, spellings like bilt, groop, hed, soop, thum, tuff, tung and wimmen failed to make the leap from his dictionary into national usage. His attempt to purge the Bible of phrases "offensive especially to females" also had little impact—although the transposition of "testicles" to "peculiar members" deserves wider recognition than posterity has thus far allowed.