A history book, properly constructed, consists largely of narratives. To be sure, it will contain other things as well - raw data, maps, etc., and importantly, competing interpretations - but narrative remains the centerpiece of history, despite the claims by some scholars that historians should not present narratives.
When we do history, we are doing narratives. This is not the end of an explanation, but rather the beginning of one. We must examine how and why we do history - how and why we construct narratives. The methods and motives for telling about people, places, and events will shape the competing accounts we place side by side.
The biographer Einhard, writing sometime after the year 814 A.D. about Karl the Great, is self-consious about his process as he writes. Among the motives for his textual creation, he notes that
it is also not completely certain that anyone else will yet report about these things. And so I consider it better that these events be delivered to posterity in varying, if also similar, portrayals, instead of allowing that the glorious life and the incomparable and currently unrepeatable deeds of this most respected king of his time disappear in the darkness of the past.
Among other possible motives, Einhard - also known as Eginhard - is concerned here to ensure that data is not lost. Yet he also alerts us to ambiguity, before he even starts his actual narrative, warning us that we will encounter "varying if also similar" accounts. He tells us that he has more than one reason for constructing this biography:
There are yet still further valid and, as I believe, sound reasons, and each of them individually would have been sufficient to move me to the recording of this text: there are above all the education, which King Karl gave to me during my childhood, and also the lifelong friendship which bound me to him and to his children since my arrival at court. Therefore I am rather obliged to him, and he has made me in life, as in death, into his debtor. One could therefore properly call me unthankful if I silently passed over this man's great deeds, who rendered outstanding services to me, and if I allowed that his life received no written appreciation or fitting recognition - as if he never existed!
Einhard gives us an unusual explanation about the formation of his narrative. First, it is laced with the technical vocabulary of mathematic logic - words like 'valid' and 'sound' and 'sufficient' - which remind us that Einhard was a philosopher and theologian, and lead us to understand that there is, at least in Einhard's opinion, some deep internal logic informing his method and motive. Second, Einhard does not shy away from forming a value judgment about Karl (also known as 'Charlemagne'); an interesting tension exists between Einhard's declaration that he is willing to offer competing narratives, and his declaration that Karl/Charlemagne is a personal friend and benefactor.
Perhaps Einhard is willing to risk presenting his reader with a somewhat unusual approach because his logic demands that he consistently follow his premises through to their conclusions, and that he clearly state both. In any case, he presents us with an unusually sophisticated meta-level analysis of historiography.