In ancient Rome, May started with the Floralia festival but was pretty somber, otherwise. Just as today, even though May means spring and rebirth, not May, but June is known as the month for weddings, so then May was not a propitious time to get married. Instead it was a time when farmers were very busy with their crops and what festivals there were tended to be for the dead, with a festival for Lemures and Lares, who were worshiped on May Day.
See
The Not So Merry Month of May
May Calendar
Ancient / Classical History Forum