To put this in context, I wouldn't consider myself a history buff at all, although I know basic dates and events. However, for the last two weeks, I've been reading Gibbon's Decline and Fall of the Roman Empire, and having gone through almost a third of it, I must honestly say that I'm blown away. Not necessarily because I feel I understand a lot about the Roman Empire by reading it - I'm sure that by now, modern historians must have superseded Gibbon's views, having access to more sources and so on. But I'm impressed by its literary beauty, the magnitude of its epic scope, and Gibbon's astonishing erudition and vivid communication of his values and view of history, no matter how different they may be to a modern reader.
In short, I feel that I've developed as a general scholar, intellectual, and person by reading it. It's such a good work that I've become motivated to learn more about Roman history, although I was never particularly interested in it in the first place.
I wonder if there are any other classic history books by which professional historians recommend as a "must-read". Not necessarily because "X is the best book for knowing the history of Y" but more of like the above reason: "X is a book that should be read even if you're not particularly interested in period Y, because it's just an amazing work." I understand that reading such works will not necessarily make me a good historian - because I am not, for example, reading Gibbon in a proper context such that I can critically analyze him and so on. But if there are any other works like Gibbon's I think it's worth it to read, just as a literary and intellectual experience.
I've scoured the past threads in this subreddit, but most of them are focused on the "what are the best books for learning about Y" perspective - which is fine, but not quite what I'm looking for. That being said, I've noticed a comment in the Master Booklist about Barzun's From Dawn to Decadence:
From Dawn to Decadence: 1500 to the Present: 500 Years of Western Cultural Life by Jacques Barzun: A magisterial work of cultural history, an end-of-life summa penned by one of the most civilized men ever to exist. It's both scholarly and accessible, narrated in gorgeous prose, and deserves a place on your bookshelf next to Thucydides, Tacitus, Gucciardini, Gibbon, Macaulay, and Burckhardt.
Based on this passing comment, I've noted down these works as representative of the "classics" I'm looking for:
History of the Peloponnesian War, Thucydides
Histories, Tacitus
The History of Italy, Gucciardini
The Decline and Fall of the Roman Empire, Gibbon
The History of England, Macaulay
The Civilization of the Renaissance in Italy, Burckhardt
From Dawn to Decadence, Barzun
I wonder if anyone can add to this list or correct it? What, in your view, are the great masterpieces of historical writing, similar to how Beethoven's Fifth Symphony and Bach's Mass in B minor are masterpieces of Western classical music? For example, I probably wouldn't count popularized outlines like HG Well's or Asimov's. But are works like Toynbee's A Study of History and Durant's The Story of Civilization regarded as classics of historical writing? Or perhaps, like Gibbon, there are works which focus on a particular period but are masterpieces anyway.
For antiquity, I'd suggest adding Caesar's Commentarii de Bello Gallico and Herodotus' Histories.
Thucydides is famed for his attempt at methodological thoroughness, attempts at even-handedness, use of eyewitnesses and chronological detail. But frankly, as language goes, you won't find the kind of inspiration there you did in Gibbon. It can be a bit... cumbersome.
Herodotus is much more readable, much more entertaining. What you'll find instead of pedantic plodding is a breathtaking curiosity and (sometimes meandering) variety of subjects, combined with a good mind and more critical thinking than he is sometimes credited with.
You can't trust everything Herodotus tells you, and the farther the story gets from Greece the more dubious the reliability gets, but that doesn't lessen it as a work of literature.
Indeed, in your place I might consider skipping Thucydides altogether.
Caesar, of course, has been required reading for centuries because of the clarity and power of his simple prose. It's short, but very worthwhile, not only for the history it depicts, but for the lesson in propaganda is provides. When reading, you should never forget that the work was intended to be read by Caesar's contemporaries in Rome, as these events were happening. This makes it an absolutely fascinating document, because it doesn't just describe things that happened, but illustrates what the Romans thought important.
I could go on and on, (Xenophon! Polybios!) but you probably want to get beyond the first few centuries A.D. in your reading at some point.
Except... have you read the Iliad & Odyssey? They're not history, but most of the ancients thought of them as such, and they're really the foundation of classical culture. You might even compare their status in that world to the one held by the bible in ours. (Not, I stress, as a holy book, but as a fount of shared stories and point of reference.) And besides, they're some of the greatest stories ever told. So if you haven't, perhaps those should be your starting point.
I would recommend anything by Peter Brown, who writes about the same topics as Gibbon (and is still alive, though recently retired). Brown's prose, like Gibbon's, is a joy to read; it's a struggle to skim his books, because the words draw you in. And as a bonus, the books are excellent scholarship.
For the middle ages, I would highly recommend Marc Bloch. He was killed while fighting in the French resistance during WWII, but left us some of the most wonderful prose (even in translation, if you don't read French), and founded an approach to history (the Annales school) that continues to provoke a lot of thoughtful work. Like Gobbon, his work continues to be influential even though the field has moved past many of his specific conclusions.