In one legend, Anna Perenna is an old woman who brought the plebeians cakes and kept them fed. For these reasons She was always popular with the common people, and after Her death She was considered a Goddess.
In a later legend Anna is a young woman, the sister of Dido, Queen of Carthage. After the death of her sister, Anna fled to Rome, where the hero Aeneas had settled. Here she ran afoul of his wife Lavinia, and in despair she killed herself by drowning in the River Numicius. Afterwards she was said to have been given the surname Perenna, and worshipped as the nymph of the river.
In yet another tale, She is again an old woman. The God of War, Mars, was in love with Minerva, the Goddess of War and the Arts and a sworn virgin. He asked Anna Perenna to intercide on His behalf; instead She dressed Herself up as Minerva, and, veiled, came to Mars. When He tried to kiss Her She laughed and laughed at Him in scorn. Minerva's main Roman festival, the Quinquatrus, was held just 4 days after Anna Perenna's and this is usually the explanation given for why they are linked in this legend.
The Festival of Anna Perenna on the 15th of March was beloved by the common people, though it was also an officially recognized holiday. On the evening of the 15th, people would gather at the 1st milestone on the Via Flaminia in Her sacred grove of fruit trees (in bloom at that time of year) by the banks of the Tiber, and camp out, some bringing tents, others making little shelters from leafy tree branches. There they picnicked merrily into the night, feasting, dancing, singing, and celebrating with much wine, toasting to health and long life. It was believed that one would live as many years as the cups of wine one could drink, and so it was of course traditional therefore to get very, very drunk.
Well, sounds like a winner holiday to me! Thanks again to OGOD. Happy celebrating!