In the second half of the 14th century, two sisters from Castile came to dominate the English royal family.
Isabelle Perez
Every King or Queen of England since Henry VIII is descended from Isabelle Perez. Perhaps as significant is that it was her immediate family—the Yorkists—which challenged for the throne during the Wars of the Roses.
Constance Pedra
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The determination of the english royal family to reclaim the blood line can be seen that she was first married to Henry’s older brother Arthur and when he died was married to Henry, something that the Church did not normally allow.
Illegitimate Sisters
What is incredible is that Isabelle and Constance were illegitimate daughters of Pedro of Castile. In Spanish genealogical records they are not know as “Perez” but by the name of their mother “de Padilla”
What caused such interest and a determination to share the bloodline of two illigitimate sisters?(see also The right to rule)
As the various contenders for sovereignty searched around for bloodlines which might justify their “right to rule”. A new line was discovered and promoted. The new line was said to offer a direct Matrilineal link to Mary Magdelene, whose womb was considered to be the Sangreal, via the fruit of her womb, her daughter Tamar.
It does not matter what we think of such theories today, in 1350 these theories were believed and battles fought over them.
Descent from Mohammed
Just to be sure this bloodline was said to give a second benefit, direct descent from Mohammmed. At a time when it seemed possible that the whole of Europe might fall under the rule of Islam, this was a significant consideration.
Maria De Padilla
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The matrilineal lineage
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It turns out that there are two separate descents from Mohammed, the first through Zaida of Denia This link is well known and Zaida’s lineage to Mohammed is well documented because the lineage was claimed by Frederich II Hohenstauffen.
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What is disputed is wether Zaida is the mother of Sancha Alfonsez of Castile, some records show her mother as “Elizabeth”. The Spanish records are adamant however that Zaida was baptised and took the baptismal name of Elizabeth.
There is a break in the matrilineal decent however as it gets back to roman times , which is necessary if we are searching for Mary Magdelene and her daughter Tamar. If there is any truth it Mary Magdelene must have been known by some other name