No manuscript anywhere preserves the whole of 1 Enoch except in Geez, the classical liturgical language of Ethiopia, where it survives in more than a hundred copies in two recensions, the earliest from around the fifteenth century. Everything older is fragmentary, and the fragments are what fix the dating.
Eleven Aramaic manuscripts from Qumran Cave 4 carry parts of the Watchers, the Astronomical Book, the Dreams and the Epistle. The oldest palaeographically belong to the early second century BCE and one astronomical copy may be older still, which puts the composition of those sections in the third or early second century BCE and makes them among the earliest Jewish apocalyptic writing known. Their existence also settled a long argument: the Ethiopic text, however late its manuscripts, descends from a genuinely ancient Jewish work rather than a Christian confection.
Greek survives in substantial pieces. The Akhmim manuscript, also called Codex Panopolitanus, was recovered from a grave in Egypt in the winter of 1886 to 1887 and carries most of chapters 1 to 32. A Chester Beatty papyrus preserves much of the Epistle. The Byzantine chronographer George Syncellus quotes further passages.
What is conspicuously missing shapes the scholarship. No fragment of the Parables has been identified at Qumran, and the Parables are absent from the Greek witnesses too. Jozef Milik took this as evidence for a Christian composition of the third century CE, a position most scholars have rejected; the current range runs from the late first century BCE to the early second century CE. The date is not a technicality, because it decides whether the Son of Man language of the Parables is background to the Gospels, contemporary with them, or later.