After his wife Anne Neville's demise, if King Richard III had married his niece Elizabeth, the daughter of King Edward IV, how much would this marriage have strengthened Richard's hold on the throne?
Hmmm. I have thought about that. It would be very shocking to marry your own niece, nephew, uncle, aunt. Maria I of Portugal married her uncle. It might have solidified his hold on the crown, but he would have had to obtain approval from the Pope, as they were too closely related for any such marriage to be recognized. If it was recognized, that could have brought additional players to come to Richardís side. A Papal dispensation would have taken time that Richard didnít have. So ultimately, no.