When you were small, did you ever deliver a May basket to a neighbor or family member? I did. It's a charming practice.
Do you know where the custom comes from? Mostly, they're found in Germanic and Celtic countries of northern Europe. Nobody knows where they originated, but most agree they're a continuation of the reverence for sacred trees. Some view them as having phallic symbolism. Whoa, baby! That's some big, um-m, rod. These things could be as tall as trees! Which they were. The original ones were trees that had been stripped of all but their top leaves. John Cleland's controversial novel, Fanny Hill records, “...and now, disengag'd from the shirt, I saw, with wonder and surprise, what? not the play-thing of a boy, not the weapon of a man, but a maypole of so enormous a standard , that had proportions been observ'd, it must have belong'd to a young giant."
The earliest recorded evidence comes from a Welsh poem written by Gyffydd ap Adda ap Dafydd during the mid-14th century, in which he described how people used a tall birch pole at Llanidloes in central Wales.
On May Day young men use commonly to runne into woodes at night time, amongst maidens, to set bowls. So much as I have heard of tenne maidens whiche went to set May and nine of them came home with childe. ~ Unknown 16th century chronicler.
And there you have it.