Spencer Illéa is a historical character in The Selection Series. He was the oldest son of Gregory Illéa. He rejected the crown and became the founder of Northern rebels. He is the grandfather of August Illéa, the current leader of Northern rebels and the true heir to the throne of Illéa.
Spencer was about to become the king of Illéa after his father would retire. However, he soon realized that his father had forced his older sister Katherine to marry the King of Swendway so that he could become the king himself. He knew that the same was expected of him, but he couldn't do it. So he faked his own death and ran away, although his father probably knew the truth and wrote about it in his diaries. His younger brother Damon Illéa became the king instead. Spencer hid with relatives and friends, eventually making a camp with some like-minded people in the north and becoming the founder of Northern rebels.
The majority of Illéa's people believe that Spencer really died and after the death of Justin Illéa, the family was extinct. The Northern rebels though and those who have read Gregory Illéa's diaries, such as America, Maxon and King Clarkson, know the truth. Maxon was prepared that one day one of Spencer's descendants would come for the crown as its true heir. August Illéa, although he admitted to be a direct descendant and legal heir to the throne of Illéa, declared that he didn't want to be the king. On the opposite, he respects the monarchy and especially Maxon. He simply supports the goals of Northern rebels: having nominated officials and putting an end to the castes.