Victoria was physically unprepossessing—she was stout, dowdy and no more than five feet tall—but she succeeded in projecting a grand image. She experienced unpopularity during the first years of her widowhood, but was well liked during the 1880s and 1890s, when she embodied the empire as a benevolent matriarchal figure. Only after the release of her diary and letters did the extent of her political influence become known to the wider public. Biographies of Victoria written before much of the primary material became available, such as Lytton Strachey's Queen Victoria of 1921, are now considered out of date. The biographies written by Elizabeth Longford and Cecil Woodham-Smith, in 1964 and 1972 respectively, are still widely admired. They, and others, conclude that as a person Victoria was emotional, obstinate, honest, and straight-talking.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): When were the best biographies of Queen Victoria written?
1964 and 1972