Now as promised here are my ideas on why AA's claim lasted so long. Of course Chat will never accept them because there's no page number from Kurth's book but maybe it will give the rest of us something to think about and discuss.
Some reasons it worked for so long
Why was her claim so long lived and famous while other claimants faltered? She certainly had the right backing, determined, clever, strong willed supporters with a plan and the knowledge and creativity to make it appear to work. The publicity of the trial, and the writings of supporters like the Botkins and Rathlef, made her story an intriguing, spellbinding legend of fairy tale proportions that attracted the interest of millions. Plays and movies were made based on the legend that grew around Anderson. It seems people wanted her to be Anastasia, it was more fun to believe in the 'lost princess' and easier to villainize those who tried to 'stop' her. This may be why it's so hard to tell or see the other side of it to this day- it wasn't as interesting if she were a fake, 'only' a Polish beet farm girl and factory worker playing a part. Some people wanted to believe it very badly.
It does look as if many of her earlier supporters in the Russian emigre' community were not so much accepting her as "Anastasia" specifically but as a piece of the past they hoped to hold onto. Notice many of the comments on why they accepted her "Those are Nicky's eyes." "She waved goodbye just like my Empress" "She raised her hand to be kissed like a lady of good breeding" and so forth. There is little relating to her being ANASTASIA herself, except maybe a bit from Leeds and of course the questionable Botkins. Part of believing in Anderson's claim seems rooted in nostalgia and desire for the past to return, all parts of the wishful thinking that sometimes made people see what they chose to see in their hearts, even if it wasn't really there.
The Americans who made her the toast of New York wouldn't have known nearly enough to identify or reject a real Anastasia, so that's no endorsement. They were told she was a princess, they played the game without question. In the days of glamorous movie actresss, she was the star she always wanted to be. People wanted, maybe even needed, a lost princess among them. In her later years she was rough, disheveled and not at all regal in appearance or demeanor, yet she still collected new admirers. As Olga Alexandrovna said, "My telling the truth does no good, because the public simply wants to believe the mystery."
Who Really Knew Anastasia?
Another big part of why the charade was so successful may have been because so few people knew the girls very well. They were all so close in age and most people who had casual contact would not have been able to remember the particular characteristics of each and tell one from another years later (such as Zina Tolstoy who first accepted AA as "Tatiana" then changed to "Anastasia" when the Grand Duchess in the claim changed) The family was mainly very isolated, the children sheltered by their mother, they didn't go out, no one came in. Only a few inner circle people had more than brief contact. There were really no close friends, or even close cousins, who knew her well enough to accurately vouch for her authenticity, or lack thereof. Sophie Buxhoevedon wrote that "friends would have been welcome, but no young girls were ever asked to the Palace. The Empress thought that the four sisters should be able to entertain one another." Anna Vyrubova mentions the same scenario in her memoirs: "...friends for these high born but unfortunate girls were very difficult to find. The Empress dreaded for her daughters the companionship of oversophisticated young women of the aristocracy, whose minds, even in the schoolroom, were fed with the foolish and often vicious gossip of a decadent society. The Empress even discouraged association with cousins and near relatives, many of whom were unwholesomely precocious in their outlook on life."
This shortage of real witnesses played right into the hands of Anderson and her supporters. Had she gone to school instead of being tutored at home, there may have been dozens of friends and acquaintances who would have seen Anastasia on a daily basis and would have known her well enough to tell her from an imposter. Because of their lack of outside contact, Anastasia wasn't individually familiar to many who could have have honestly been able to identify or refute her for sure. The few who did have close relationships with her either weren't asked (Anna Vyrubova, Dmitri Pavlovich) or were branded as 'liars' (Olga Alexandrovna, Pierre Gilliard, Sophie Buxhoevedon) who were out to deprive "Anastasia" of her 'name' and 'money'. Sadly, many people fell for this reasoning and the charade and case continued.
Popularity of the "Anastasia" legend and a desire to believe it
Ever since the 1920's, the story of the escaped princess fascinated and captivated the public's attention. After Rathlef's serialized story on Anderson was published, there were "Anastasia" brand cigarettes and candy being sold in Berlin, and even a night club tune written in her honor. If she were only Franziska, that was no fun!
Later, another issue working against Berenberg-Gossler and the others trying to disprove Anderson's claim was when a round of the case coincided with the 1956 release of Twentieth Century Fox's box office hit "Anastasia", starring Ingrid Bergman. The grossly inaccurate but very popular movie helped legitimize Anderson's claims in the court of public opinion and made things a lot more difficult for Berenberg-Gossler. The court case had a large following in German tabloids and many readers who saw the movie thought it was a true story. People wanted to believe, and didn't want to hear that it wasn't true. It was much easier for them to accept the 'evil relative' excuse than to face the truth- the real Anastasia was dead, and Anna Anderson was only a Polish factory worker who'd lucked into the role of her life.
Prince Michael Romanov, a grandson of Grand Duchess Xenia Alexandrovna, stated that while the family always knew Anderson to be an imposter, the legend around her made it much more difficult to convince others. With a host of movies, books and newspaper articles promoting Anna Anderson's claims from the 1920's to the present day the Romanoff family found it increasingly difficult to escape the soap opera, for all the glories of a once magnificent imperial dynasty it was Anderson's claims most people wanted to talk about.
"Over the years friends and acquaintances who had seen the movies or read the books on Anderson would lecture me on why she was genuine," Prince Michael recalls, "few would listen to or accept the otherside of the argument. It was infuriating but after a while I just stopped arguing, what point was it?, how could I compete with the glamorous tales being created by the entertainment industry."
The Media's portrayal
Perhaps the biggest factor in the long life of the charade was the public interest, the media's presentation and sensationalism. Dr. von Berenberg-Gossler said that during Anderson's German court cases the press were always more interested in reporting her side of the story than the opposing benches' less glamorous perspective. Editors often pulled journalists after reporting testimony delivered by her side and ignored the rebuttal, resulting in the public seldom getting a complete picture. This is a big factor in why the story is always told so slanted to her side, and why I am here today trying to balance it out.
(source for above 3 paragraphs: John Godl's article, "Remembering Anna Anderson, part II) The rest is my own research and observations.
AND THE NUMBER ONE ANSWER IS......
It was all about the money. No other claimant had a multimillion dollar claim and lawsuit. Money, the root of all evil, money that turns otherwise nice people into greedy monsters. Anderson claimed that she, as "Anastasia" was told by her father of enormous amounts of money deposited in European banks in the names of the Grand Duchesses. Anyone who could prove they were one of the Tsar's children stood to inherit countless millions. Thus, Anderson became a sort of 'cash cow' to her supporters, and backing her until she proved her identity and claimed her fortune was making it profitable indeed to be a supporter. While in reality there was no such mysterious fortune, and the surviving Romanovs seemed not to be well off financially, the lure of it was enough to drive the claim onward. Ironically, while most Anderson supporters to this day will use greed and lying for money as the motivation of those who denied her, it appears that may well have been the other way around!(some lying or embellishing to support her in the event of a big payoff if she won)