The Roman-Gallic word "May" replaced the Old English name in England after the Norman Conquest. Primilce meant "the month in which cows can be milked three times in a day." May has always had 31 days, unlike other months that have varied over the past three millenia.

May is crowded with holidays and observances. The first day of May is called May Day and has significance in much of the Western World. It is descended from spring festivals that were held in Roman, Teutonic and Celtic regions.¹ Celebration is characterized by maidens dancing around a maypole and both sexes engaging in various frolicking pursuits. A rather idealized depiction of the occupation called going a-Maying is depicted in the musical Camelot (1982). May Day became an important socialist/communist holiday as well because it commemorated a resolution to reduce working hours in industry.

Cinco de Mayo (5th of May) is celebrated in Mexico as well as parts of the United States. It commemorates a battle when the Mexican army defeated the French at the battle of Puebla in 1862. It is celebrated with parades, dancing, mariachi music and other festivities.

This month has also been adopted by many organizations for special observances of Asian Awareness Month, Egg Month, Historic Preservation Month, Older American Month, Teacher Appreciation Month and many more.

In the northern latitudes, May is a time when Spring is in full swing. The abundance of new life and flowers prompted the old saying attributed to Thomas Tusser (1524?–1580), "April showers bring May flowers".

The birthstone for May is the emerald.