Olympias (daughter of Robert Guiscard)

Helena, born Olympias, was a daughter of the Norman duke of Apulia, Robert Guiscard, and the Lombard noblewoman Sikelgaita.

[2] According to the late 12th-century Fragmentary Troia Chronicle: Alexius factus est imperator, et Robertus dux transivit mare, et cepit eum impugnare ob Olimpiadem filiam suam, quam expulearat de palatio suo.

[3] Alexius was made emperor, and Duke Robert crossed the sea, and started to attack him on account of Olimpias his daughter, whom he had banished from his palace.

[9] The initial Norman–Byzantine marriage proposal was made by Emperor Romanos IV around the time the Normans were besieging Bari, which surrendered in April 1071.

Romanos offered to marry one of his sons to one of Guiscard's daughters, but his defeat at the battle of Manzikert put an end to discussions.

[10] Emperor Michael VII renewed talks, offering to marry his younger brother (Konstantios or Andronikos) to one of Guiscard's daughters in late 1072 or early 1073.

In return, Guiscard agreed to respect the empire's borders and to assist in their defence, which probably meant that he would procure Norman mercenaries for the emperor.

[20] Her future father-in-law made a large donation to the abbey of Montecassino about this time, perhaps in recognition of the diplomatic efforts of its abbot, Desiderius, on behalf of the marriage.

In March 1078, Michael VII was overthrown in a coup d'état and Helena became a hostage of the new emperor, Nikephoros III.

[21] During the winter of 1080–1081, Guiscard sent envoys to Constantinople in an effort to rescue his daughter and at the same time to sound out an alliance with Alexios Komnenos.

[8] She is in fact overtly hostile to Helena, claiming that the child Constantine abhorred his future fiancée from the beginning.