In traditional Roman Catholicism, May is the month dedicated to Mary, the Mother of Jesus. The old maypole folk celebrations were replaced with May processions of the statue of the Virgin Mary. Many of the maypole traditions were incorporated such as "girls in white dresses with blue satin sashes" (Sound of Music)wearing garlands of mayflowers and carrying bouquets of wildflowers.
You would be hard-pressed to find a May procession in today's modernist church. I haven't seen one in my Diocese in about ten years.
Anyway, when the Nazis took over, they tried to suppress all traditional religious customs and supplant them with things that were more "Germanic", or to the Fuhrer's liking.
Wait a sec...are you telling me that the Maypole festival is a celebration of the virgin mary? Is that what you are saying?