Marry in May and You'll Rue the Day
"The old wedding superstition that getting married in the month of May brings bad luck to the marriage."
Traces to ancient Rome, where the month of May was dedicated to Lemuria, a solemn festival for honouring and appeasing the restless dead. Weddings, a celebration of new life and joy, were considered inappropriate and unlucky to hold during a month set aside for mourning and warding off spirits, a clash of moods that made a May wedding feel like tempting fate. The superstition long outlived the Roman festival that inspired it and spread across Europe as part of a wider tradition of wedding-month rhymes, "Marry in May, rue the day," being the most famous line from a longer folk poem ranking every month's marital luck.