The Odyssey is largely a sequel to the Iliad, both of them being attributed to Homer and describing events which are roughly part of a single overall story (Odysseus first fighting in the Trojan War and then returning home). Modern retellings of these stories are often sold together, like two parts of a single series. But were the original versions more independent?
Does the Odyssey, in its original version, assume or require knowledge of the Iliad? Or is all the necessary story background on Iliad events provided in the Odyssey itself?