Question: Anna Anderson (16 December 1896 – 12 February 1984) was the best known of several impostors who claimed to be Grand Duchess Anastasia of Russia, was the youngest daughter of the last Tsar and Tsarina of Russia, Alexandra and Nicholas II, the last Emperor of Russia, ruling from 1 November 1894 until his forced abdication on which date?

Context paragraphs:
Grand Duchess Anastasia Nikolaevna of Russia: Grand Duchess Anastasia Nikolaevna of Russia (Russian: Анастасия Николаевна Романова [Anastasia Nikolaevna Romanova]; June 18 [O.S. June 5] 1901 – July 17, 1918) was the youngest daughter of Tsar Nicholas II, the last sovereign of Imperial Russia, and his wife, Tsarina Alexandra Feodorovna.

Anya (Anastasia): Anastasia is the title character from the 1997 Fox Animation Studios film of the same name, and a fictional version of Grand Duchess Anastasia Nikolaevna of Russia.  She is voiced by Meg Ryan, while Liz Callaway provides her singing voice.  She is the Grand Duchess Anastasia Nikolaevna of Russia ("Anya"), the youngest daughter and one of two surviving members of the Imperial family.

Suzanna Catharina de Graaff: Suzanna Catharina de Graaff, born Suzanna Catharina Hemmes, (5 May 1905, in Rotterdam – 25 November 1968), was a Dutch woman who claimed to be a fifth daughter of Tsar Nicholas II and Tsarina Alexandra.  Her claim was accepted by Anna Anderson, who claimed to be Grand Duchess Anastasia Nikolaevna of Russia, but by few others.  The Russian Imperial family was killed by Bolsheviks in Ekaterinburg, Russia, on July 17, 1918.  After the reported murders, a number of people claimed to be surviving members of the family.

Grand Duchess Olga Nikolaevna of Russia: Grand Duchess Olga Nikolaevna of Russia (Olga Nikolaevna Romanova) (Russian: Великая Княжна Ольга Николаевна ; ] (Velikaya Knyazhna Ol'ga Nikolaevna); November 15 [O.S. November 3] 1895 – July 17, 1918) was the eldest daughter of the last Tsar of the Russian Empire, Emperor Nicholas II, and of Empress Alexandra of Russia.

Anna Anderson: Anna Anderson (16 December 1896 – 12 February 1984) was the best known of several impostors who claimed to be Grand Duchess Anastasia of Russia.  Anastasia, the youngest daughter of the last Tsar and Tsarina of Russia, Nicholas II and Alexandra, was killed along with her parents and siblings on 17 July 1918 by communist revolutionaries in Yekaterinburg, Russia; but the location of her body was unknown until 2007.

Nicholas II of Russia: Nicholas II or Nikolai II (Russian: Николай II Алекса́ндрович , "Nikolay II Aleksandrovich" ; 18 May [O.S. 6 May] 1868 – 17 July 1918) was the last Emperor of Russia, ruling from 1 November 1894 until his forced abdication on 15 March 1917.  His reign saw the fall of the Russian Empire from being one of the foremost great powers of the world to economic and military collapse.  Due to the Khodynka Tragedy, anti-Semitic pogroms, Bloody Sunday, the violent suppression of the 1905 Revolution, the execution of political opponents and his perceived responsibility for the Russo-Japanese War, he was given the nickname Nicholas the Bloody by his political adversaries.  Soviet historiography portrayed Nicholas as a weak and incompetent leader, whose decisions led to military defeats and the deaths of millions of his subjects.

Clothes Make the Woman: Clothes Make the Woman is a 1928 American silent historical romantic drama film directed by Tom Terriss, and starring Eve Southern and Walter Pidgeon.  The film is loosely based on the story of Anna Anderson, a Polish woman who claimed to be Grand Duchess Anastasia Nikolaevna of Russia, the daughter of the last czar of Russia Nicholas II and his wife Alexandra.  Anastasia was killed along with her parents and siblings by communist revolutionaries on July 17, 1918.

Anastasia (1956 film): Anastasia is a 1956 American historical drama film directed by Anatole Litvak.  Set in interwar France, the film follows the story of a suicidal amnesiac (Ingrid Bergman), whose remarkable resemblance to the Grand Duchess Anastasia Nikolaevna of Russia — the youngest daughter of the late Tsar Nicholas II and Empress Alexandra Feodorovna, who is rumored to have survived the execution of her family — draws her into a plot devised by the former Russian White General Bounine (Yul Brynner) and his associates to swindle from the Grand Duchess an inheritance of £10 million.  However, the ultimate hurdle to their plan is the exiled Russian aristocracy — in particular the Dowager Empress Marie Feodorovna (Helen Hayes) — whom their handpicked claimant must convince of her legitimacy if they wish for their scheme to succeed.

The Story of Anastasia: The Story of Anastasia and in the UK, Is Anna Anderson Anastasia?  (German: Anastasia, die letzte Zarentochter), is a German film directed by Falk Harnack.  The 1956 film is based on the true story of a woman in Berlin who was pulled from the Landwehr Canal in 1920 and who later claimed to be Anastasia, the youngest daughter of Czar Nicholas II of Russia.  The entire family was executed in the Russian Revolution, but this was not confirmed until their graves were discovered in 1991 and 2007.

Eugenia Smith: Eugenia Smith (January 25, 1899 – January 31, 1997), also known as Eugenia Drabek Smetisko, was one of several Romanov impostors who claimed to be the Grand Duchess Anastasia, youngest daughter of Nicholas II, the last Tsar of Imperial Russia, and his wife Tsarina Alexandra.

Supporting paragraphs: Anna Anderson Nicholas II of Russia
Answer: 15 March 1917