In the first few years of marriage, Sikelgaita appears inactive politically. Skinner explains that her primary objective in the first few years was to produce male heirs to secure Robert's claim on the Lombard lands. She started to appear in charters next to Robert in 1065 and because Robert was frequently in conflict with his neighbours and his vassals she would remain close to him throughout their marriage. Sikelgaita showed her ambition to ensure her son inherited Robert's lands early. When Robert once was close to death in 1073, she made their vassals swear allegiance to her eldest son
Roger as heir over her older stepson Bohemond. Other than bearing children, Sikelgaita's purpose to Robert was to strengthen his claim to his land and ensure that her ancestry gave peace to the vassals who would otherwise rebel because of his status as a foreigner as well as grant her prestigious ancestry to their children.
Conflict with Gisulf of Salerno Despite their alliance through Robert and Sikelgaita's marriage, Robert and Sikelgaita's brother
Gisulf II of Salerno had a strenuous relationship. Robert continuously made encroaching acquisitions of land around his principality, most notably the city of Amalfi in 1073. Sikelgaita tried to mediate between her brother and husband, but Gisulf is said to have told her that he would make her a widow. Robert soon responded by laying siege to Salerno in the summer of 1076. Gisulf was unprepared to deal with a prolonged siege and the city surrendered in December 1076, while the last of Gisulf's forces held out in the inner citadel until May 1077. Robert and Sikelgaita made Salerno their new capital after the conquest. Because Sikelgaita was so important to Robert's legitimacy she was on occasion recognised as co-ruler in Salerno, and on two occasions she was titled duke and not duchess in charters in Salerno. Skinner argues that this is Robert acknowledging Sikelgaita's right to the principality is stronger than his own.
Military campaigns 1080–1085 Sikelgaita frequently accompanied Robert on his campaigns but often as a prize or show of legitimacy for the Lombard following. Valerie Eads notes that after the siege of Salerno and years of childbearing ended, her military career took form in 1080. Her first military objective was conducting the siege of
Trani in 1080 while Robert moved against
Taranto to defeat the rebels. The siege was successful and the rebel Peter II of Trani had to concede defeat. It is unknown to what extent she was in charge of the siege or why she was left there. Eads suggests that there were only so many he could trust who also had the loyalty of the Lombard troops. She argues that any kin with a claim to Robert's lands could easily betray him and that he needed his wife to be the guarantor of loyalty. Sikelgaita also participated in the
invasion of Dyrrhachium in 1081 against the
Byzantine Empire. At first, it is said that she tried to persuade Robert not to attack the Byzantine Empire because she argued Christians should not fight other Christians. Sikelgaita likely participated due to similar reasons as before, a lack of loyal generals and steadfast ambition to protect the interest of her son and heir. Another possibility could be that the men she was sent to command were soldiers from Salerno and could be considered Sikelgaita's men due to her claim. In 1083, Sikelgaita returned to Italy with Robert to defend
Pope Gregory VII against the
Holy Roman Emperor, Henry IV. By 1084 Robert and Sikelgaita once again turned their eyes towards the Byzantines in a second campaign during which Robert soon fell sick and died on
Kefalonia 17 July 1085 with Sikelgaita at his side.
Role in battle Whether or not Sikelgaita fought in battle is not known. The Byzantine historian
Anna Comnena, the daughter of
Emperor Alexios I with whom Robert and Sikelgaita battled in 1081 at Dyrrhachium, wrote in the
Alexiad that Sikelgaita was on the field in full armour, rallying her and Robert's troops with a spear when the Byzantine army initially repulsed them and was in danger of losing cohesion. According to Skinner, Anna Comnena's description and tale of Sikelgaita is an attempt at discrediting and effeminating the Norman army by claiming they needed a Lombard woman to make them fight. Eads adds that Comnena's account is fanciful since Sikelgaita would not have been heard in battle among the chaos and that the only way for her to communicate with her troops would have been by waving a spear-like banner behind her troops. Comnena also said that Sikelgaita was "like another
Pallas, if not a second
Athena," in reference to her bravery. Eads notes that Comnena's description of Sikelgaita echos that of Roman writing on
Boudica and it is not the only reference to other older literature as she attributes to her a quote from the
Iliad.
John Julius Norwich argued that "in her we come face to face with the closest approximation in history to a
Valkyrie. A woman of immense build and herculean physical strength, she hardly ever left her husband's side—least of all in battle, one of her favourite occupations. [...] At such moments, charging magnificently into the fray, her long blond hair streaming out from beneath her helmet, deafening friend and foe alike with huge shouts of encouragement or imprecation, she must have looked—even if she did not altogether sound—worthy to take her place among the daughters of
Wotan." Balfour argues against this notion and says: "The image of Sichelgaita as a ‘Valkyrie’ or warrior princess is misleading, insofar as there is no evidence that she was ever an actual combatant."
William of Apulia, a contemporary poet employed by Roger Borsa, wrote a different account of Sikelgaita during the battle of Dyrrhachium in his poem
The Deeds of Robert Guiscard. According to William, she is supposed to have fled with fear of her life during the battle trying to board an enemy ship after being wounded by a stray arrow but god saved her from ridicule. Historian Paul Brown points out that William's patronage is only acknowledged in the end of the poem and that the patron might be disputable. Eads suggests that William's account might have been a choice encouraged by Sikelgaita herself to not overshadow her son and that it is unlikely that he lied about a battle wound that could easily have been verified at court by the actors in his poem. She also adds that this account explains why she would wear armour because "Combatant or not, she was in danger of death or capture like any of her troops." ==Widowhood==