Meaning of "would" in "the men of Gotham would have kept the Cuckoo so that she might sing all the year"

A fairy tale begins:

Once upon a time the men of Gotham would have kept the Cuckoo so that she might sing all the year, and in the midst of their town they made a hedge round in compass and they got a Cuckoo, and put her into it, and said, 'Sing there all through the year, or thou shalt have neither meat nor water.' The Cuckoo, as soon as she perceived herself within the hedge, flew away. 'A vengeance on her!' said they. 'We did not make our hedge high enough.'

What does "would have kept" mean in this context? How do you paraphraise it? Is it something like "they were likely to have kept"?

The discussion in comments to the question (including some from myself which I no longer endorse) probably covers everything. But I guess we need an actual answer, so...

As @StoneyB comments, this is an example of the now mostly obsolete volitive sense of will, meaning approximately wish, desire, want.

On my first casual reading, I carelessly interpreted would have kept as meaning were likely to keep / were in the habit of keeping (in my defence, because that's still a common usage today).

But in fact a more reasonable paraphrase here is would have kept = wanted to keep. As @John Lawler comments, and discusses more extensively here, it's effectively an obsolete usage today.