Flora was the Roman Goddess of flowers, and its not surprising that her festival as held on the first day of May. The May Dance festivals of Europe have many of their origins in the ancient Roman "Feast of Flora", the ecstatic rites of spring.
The birth of spring on May Day in Elizabethan England would send villagers into the woods to collect boughs, and then they would wait for the sun to rise as it brought the fully opened year flowering into the world of spring. They would return home laden with flowers, all the while capering around the new maypole that had been chosen for the celebration. Only unmarried girls would be allowed to plant the phallic maypole into the fertile Earth. The maypole was hung with garlands and streamers/ Ribbons were attached to the top of the pole. Dancers took hold of the ends in a weaving courtship dance which, in its earlier origins, symbolized the Sacred Marriage of the Goddess in her Maiden aspect with the Sun God. Boys would dance in one direction and the girls in another, and so the ribbons were woven around the pole in the form of a braid.
There might also be a procession that day led by none other than Jack o' the Green, a variant of the Green Man, fantastically arrayed with flowers and leaves, followed by Morris Dancers with bells. Last, there would be the choosing of the May Queen. Crowned with a garland, the word of the May Queen, no matter how capricious, was law for the day, and all would vie for the honor of doing her homage.