alt Hacker News> That region typically used flax for string.
Replying to myself because I looked into this a bit. Looks like date palm fiber might have been more common for rope (likely much easier to make if you needed a lot).
For this use-case probably nowhere near as good though.
I've made bowdrills for fire starting with hand twisted hickory cordage. Soaking the bark makes it easy to separate the inner bark, which you then tear into long strips and twist into rope with a "reverse wrap"--basically twist until it curls back on itself then give the "bundle" a half twist back to lock it in. I'm sure many species of tree would work similarly.
That is to say there's nothing special about rope, you can make it with nothing but your bare hands.