Historiography
Apart from a few inscriptions and fragments, texts written by people who actually knew Alexander or who gathered information from men who served with Alexander were all lost. Contemporaries who wrote accounts of his life included Alexander's campaign historian Callisthenes; Alexander's generals Ptolemy and Nearchus; Aristobulus, a junior officer on the campaigns; and Onesicritus, Alexander's chief helmsman. Their works are lost, but later works based on these original sources have survived. The earliest of these is Diodorus Siculus (1st century BC), followed by Quintus Curtius Rufus (mid to late 1st century AD), Arrian (1st to 2nd century AD), the biographer Plutarch (1st to 2nd century AD), and finally Justin, whose work dated as late as the 4th century AD. Of these, Arrian is generally considered the most reliable, given that he used Ptolemy and Aristobulus as his sources, closely followed by Diodorus.
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