Another Pontifical Gem: Elizabeth's sister Anne and Manuel Duke of

Sorry if I'm repeating what people already know, but I also found this
marriage dispensation dated 1st March 1491:

"To the archbishop of Canterbury, mandate. The tenor of the petition
presented to the pope of Manuel, duke of Beja and Viseu, and Anne
Plantagenet, daughter of the late Edward, King of England, was that for
certain reasonable causes they desire to be joined together in
marriage, but that since they are related in the fourth and fourth
degrees of consanguinity, they cannot do so without apostolic
dispensation. Manuel is also, as is alleged, administrator deputed by
the spostolic see of the military order of Jesus Christ. At their
supplication, and since, as is also alleged, Anne has no fixed dwelling
place but follows the court of Henry, King of England, the pope hereby
commissions and orders the above archbishop to dispense them - if the
foregoing is true and if Anne shall not have been ravished on this
account - freely to contract marriage together and to remain therein
after it has been contracted, notwithstanding the said impediment,
declaring the offspring of this marriage legitimate."

Marie