The first evidence of the family is an extant lead seal of the strategos (general) and protospatharios epi tou Chrysotriklinou Theodore Kamytzes, dating to 1030–1050.
[1] Eustathios Kamytzes is mentioned by Anna Komnene a number of times in her history of her father, the Alexiad.
In battle, a large part of his army sought safety in flight, while he and his remaining men made a stand.
John II directed that the name of Eustathios Kamytzes be commemorated in the church liturgy on the Saturdays of Meatfare, Cheesefare, and Pentecost.
However a probable son, Constantine Kamytzes, sealed his family's place in the highest echelons of Byzantine aristocracy through his marriage to Maria Angelina Komnene, daughter of Constantine Angelos and the purple-born princess Theodora Komnene, and thus a niece of John II.