Here's quite a handy page about Maypoles, with some practical advice.

It suggests Spain as the source of the modern style Maypole in England with the ribbons, which seems quite plausible.

For some reason people seem tothink of Maypoles as being particularly English, which is nonsense. Various kinds of Maypole turn up in all sorts of cultures, including Spain, and round the West Indies, notably in the English speaking part of Nicaragua, where it si said to have come from Jamaica. And this page has a picture of Mexican Maypole Dancing, which suggests that maybe the idea about the Spanish origin for the ribbons might be spot on. (Scroll down the page and click on the picture to see it properly.)