Mario de Valdes y Cocom, a historian of the African diaspora, has argued[13] that Allan Ramsay, a noted abolitionist, frequently painted the Queen in works said to emphasize the alleged mulatto appearance of Charlotte, and that Ramsay's coronation portrait of Charlotte was sent to the colonies and was used by abolitionists as a de facto support for their cause. Valdes y Cocom goes on to state that, along with descriptions of a "mulatto face", the Queen's features had also been described as Vandalic, as exemplified by a poem written for the occasion of her marriage:

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"Descended from the warlike Vandal race,

She still preserves that title in her face."

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Valdes y Cocom does not seem to take notice that the Vandals were a Germanic people originating from Northern Europe, even if they migrated to North Africa, further straining the credulity of Charlotte's supposed Sub-Saharan African ethnicity.

All this has led Mario de Valdes y Cocom to inquire about her ancestry and research her genealogy. Still according to Valdes y Cocom, one of the possibilities for Queen Charlotte's supposed racial features is that they were a concentration of traits inherited through three to six lines from a nine times removed ancestor of hers, Margarita de Castro e Souza, a 15th century Portuguese noblewoman who traced her ancestry six generations earlier to King Afonso III of Portugal and one of his lovers, Madragana.

Critics of this theory argue that Margarita's and Madragana's distant perch in the queen's family tree, respectively 9 and 15 generations removed, makes any presumed African ancestry, Northern or sub-Saharan negligible and no more significant in Charlotte than in any other member of any German royal house at that time, and therefore that Charlotte could hardly be accurately described as "mulatto" or "African".

Even more, Valdez y Cocom assumed that Madragana was a Black African woman, because a single author, Duarte Nunes de Leão, described her as a Moor[15], that is to say, in the context of the Iberian Reconquista, someone of Islamic religion, regardless of actual ethnic origin (and that could have been Arab, North African Berber, or Muladi - native Iberian European Christians who converted to Islam after the arrival of the Moors, all of whom can be described as Caucasian or White). Modern researchers, however, believe Madragana to have been a Mozarab, that is to say an Iberian Christian living under Muslim control, of Sephardi Jewish origin.[16]

Valdez y Cocom has also argued, trying to defend the African origin of Queen Charlotte, that the Royal Household itself, at the time of Queen Elizabeth II's coronation in 1952, referred to both her Asian and African bloodlines in an apologia it published defending her position as head of the Commonwealth.[13] This is denied by Buckingham Palace.[17] The issue remains important to Afrocentrists.