Disclaimer on this: I'm his great grand daughter, so I'm a touch biased. My knowledge of his work flows comes from my mother who is not an academic ;)

To my knowledge, he's very factually accurate. He has been praised as having unparalleled knowledge of European history, and was a meticulous researcher. It enabled him to see insightful connections between events, and their repercussions. He did not write about American history, as he did not feel enough time had passed to give appropriate perspective on the events.

You do have to keep in mind though, he sometimes thought about things in a very different manner than we see things now. His views may lack some current day context, especially as he thought events should be interpreted as part of the total view of one's life and experience.

If you like the Story of Civilization, please look for the release of some new work of his in the coming year. We actually found an unpublished manuscript in the garage (yes, actually!) and got the first round of galleys back a couple weeks ago!

I'm glad there's still some interest out there. I can share some family stories if your curious. Both he and Ariel were characters.

I found this quote, from an article discussing how to teach basic history entitled "What Is Western Civilization?" by Lawrence Birken, relevant:

To begin with, the expanded definition of the West is so broad that it makes that particular civilization appear identical with civilization as a whole [...] it is also present in the works of the great popularizers such as Will and Ariel Durant whose Story of Civilization relegates the history of China, India and Japan to the first volume of an eleven volume series. Appropriately, that first volume is entitled Our Oriental Heritage as if the entire existence of other civilizations is merely a prelude to our own. This identification of the West with the totality of history itself is reflected by the tendency to regard the "Westem Civ" course as the "Introduction to History" course in many universities. Needless to say, such a highly teleological approach has important practical drawbacks. In particular, the over-identification of the West with civilization as a whole produces an inevitable reaction. Over-extension is leading to collapse so that the very idea of the Western Civ course is being challenged for its boundless ethnocentrism and cultural hubris. The increasingly cosmopolitan nature of both the university and the world itself must outmode the overinflated pretensions of the expanded definition of Western civilization.

Essentially, by giving "civilization" a "story", the Durants make very specific claims about the West, its importance, and its position in history (namely, #1 in all categories). By taking modern Western civilization as the endpoint of the historical narrative, the ancient Mesopotamian and African civilizations are never allowed to exist on their own terms; essentially, everyone else serves as mere predecessor: Ancient Greece to Rome, Rome to Renaissance Italy, the Renaissance to the Enlightenment, until we finally reach the global dominance of the West. Such ethnocentrism was perfectly acceptable (if not roundly encouraged) in scholarly history until a flurry of developments in the latter half of the twentieth century made a Eurocentric approach to "big" history quite gauche. Differences in interpretation over the decades are going to render most of the narrative unfit for explaining current scholarly consensus. Honestly, if you want to read to be informed, you'd almost be better off reading the Wikipedia articles on the major people, events, and movements covered in the series.

That said, like the much older Gibbon's Decline and Fall, well-written, vastly-conceived works of history have exceptional charm that makes reading them very enjoyable. Such projects often take lifetimes, and take highly dedicated and widely-educated people to create—it's frankly unlikely that we'll see anything quite like The Story of Civilization in our lifetimes. If you can accept that many of the ideas and interpretations of events are outdated (much like with any classic literature), there's no reason not to indulge, in my opinion.

I love Will Durant. I own all his books. However one must be mindful of the limitations of such history. When writing a history of everything, things must necessarily be truncated and twisted (for lack of a better word) for the sake of narrative cohesion.

Durant is wonderful because of his ambition and sense of scope. He asks the big questions of history. Yet that comes at the cost of accuracy. I read Durant more like a Sarah Vowell book or something like that. Not that its bad or intellectually dishonest.

Durant is the bane of my existence. Well that is an exaggeration, but his presentation of Greece and Rome is incredibly stereotyped and follows along well worn "rise and fall" patterns. There is the predictable contrast between freedom loving Greece, which is basically just Athens with a dash of Sparta, and practically minded Rome, and Late Antiquity might as well be a deformed appendage.

He is an extremely talented writer, but he was writing for a popular audience in the early twentieth century. Read it for its literary value, but don't confuse it with good history.