He emerged as a leading warrior figure among the Norsemen who had secured a permanent foothold on Frankish soil in the valley of the lower Seine after the Siege of Chartres in 911.

He has been analyzed by European scholars such as W. Vogel, Alexander Bugge, and Henri Prentout, who have debated if Dudo's account can be taken as historically accurate.

[12][13] Rollo was born in the mid-9th century as his tomb states he was in his eighties when he died in 933; his place of birth is almost definitely located in the region of Scandinavia, although it is uncertain whether he was Danish or Norwegian.

In part, this disparity may result from the indifferent and interchangeable usage in Europe, at the time, of terms such as "Vikings", "Northmen/Norsemen", "Norse", "Swedes", "Danes", "Norwegians" and so on (in the Medieval Latin texts Dani vel Nortmanni means 'Danes or Northmen').

The earliest well-attested historical event associated with Rollo is his part in leading the Vikings who besieged Paris in 885–886 but were fended off by Odo of France.

This has since been variously interpreted as referring to Faxe, in Sjælland (Denmark), Fauske, in Sykkylven (Norway), or perhaps a more obscure settlement that has since been abandoned or renamed.

Both Irish and Icelandic sources suggest that Rollo, as a young man, visited or lived in northern Scotland, where he had a daughter named Cadlinar (Kaðlín Kathleen).

This has puzzled many historians, but recently this person has been identified as Guthrum, the Danish leader whom Alfred the Great baptised with the name “Athelstan”, and was recognised as King of the East Angles in 880.

[30][31] Dudo recorded that when Rollo controlled Bayeux by force, he carried off the beautiful Popa or Poppa, a daughter of Berenger, Count of Rennes.

She may have come from any country with which the Norse had contact, as Dudo is a highly unreliable source who may have written his chronicle primarily as a didactic tool to teach courtly values.

Dudo narrates a humorous story not found in other primary sources about Rollo's pledge of fealty to Charles III as part of the Treaty of Saint-Clair-sur-Epte.

On taking his oath of fealty, Rollo divided the lands between the rivers Epte and Risle among his chieftains and settled in the de facto capital of Rouen.

[40] Given Rouen and its hinterland in return for the alliance with the Franks, it was agreed upon that it was in the interests of both Rollo himself and his Frankish allies to extend his authority over Viking settlers.

With their combined army they marched to his aid in fulfilment of their pledge to the Carolingians, but were stopped at the Oise River by Charles' opponents who traded their cooperation for more territorial concessions.

[43] Rollo died sometime between a final mention of him by Flodoard in 928, and 933 – the year in which a third grant of land, usually identified as being the Cotentin and Avranchin areas, was given to his son and successor William.

[44] In Dudo's story of Rollo, he had a vision in which he was on a high mountain on a Frankish dwelling, where he washed himself in a stream and rid himself of the diseases with which he was infected.

[47] Rollo's son and heir, William Longsword, and grandchild, Richard the Fearless, forged the Duchy of Normandy into West Francia's most cohesive and formidable principality.

[52] Rollo's dynasty survived through a combination of ruthless military action and infighting among the 10th-century Frankish aristocracy, which left them severely weakened and unable to resist the Rouen Vikings' growing determination to stay put.

[54] The duchy was later absorbed into what became the Angevin Empire following its conquest by Geoffrey of Anjou, who in 1128 had married Matilda of England, herself a descendant of Rollo.

[55] Rollo left a legacy as the founder of Normandy, and his leadership and integration of Viking settlers into the region transformed it into a stable political entity.

[56] His lineage played a key role in shaping medieval Europe, as it was William the Conqueror, another descendant of Rollo, who famously led the Norman Conquest of England in 1066.

The similarities to Rollo are slim, as the play draws inspiration from Herodian's account of the rivalry between Emperor Severus's sons, Geta and Antonine.