In addition to the reasons previously mentioned (little education, lack of standardized spelling, phonetic spelling) we should not overlook social and financial advantage. Historically the English have freely sneered at all their neighbors (Irish, Scots, Welsh, Cornish) and all their enemies (Spanish, French, Dutch, Germans, Italians, many others). It's a practice they may have learned from the Romans, but more likely it's just human nature. Eagerness to distinguish "Us" from "Them" contributes to much trouble but also has high survival value.

Many people throughout history, and probably before, have changed not only the spelling of their names but also their names, religions, cultures, residences, and friends in order to obtain advantages otherwise unavailable or to escape penalties otherwise inescapable. In addition there have long been petty officials eager to make trouble for people they considered their inferiors. Two examples of this sort of activity come readily to mind, one of them reasonably well known and the other quite obscure.

The well-known one is this: during the First World War British popular opinion was so vehemently antagonistic toward Germans that a prominent British family of German ancestry, the Battenburgs, changed their name to Mountbatten (a literal translation, incidentally). The obscure one is this: when my great-great-grandparents presented themselves to a clerk of court in Boston, asking for a marriage license, he refused them on the grounds that her maiden name being the same as the groom's surname proved that they were too closely related to be married. They returned the next day with 14 other people of the same name, all of whom swore under oath that they were not related within the sixth degree to each other or to the prospective bridal couple. The clerk yielded with ill grace; he recorded the groom's name correctly but (apparently a sexist as well as a bigot) recorded the bride's name as "Hannora ? ?" My family has had four generations of laughs over that.

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