"I doubt whether any Hogwarts students ever found out more about the Hogwarts grounds and Hogsmeade than we did.... And that's how we came to write the Marauder's Map, and sign it with our nicknames. Sirius is Padfoot. Peter is Wormtail. James was Prongs."
-- Remus Lupin (PA18)
The self-titled Marauders were a group of Gryffindor students who attended Hogwarts between 1971 and 1978. The ringleaders were James Potter and Sirius Black. Remus Lupin and Peter Pettigrew rounded out the group. The Marauders were well-known as troublemakers and pranksters, particular Potter and Black who earned themselves an entire drawer of discipline records in Filch’s office.
Several key events and people figured into the story of the Marauders. Their nemesis was Severus Snape, a Slytherin whose envy and dislike of Potter was fueled by Snape’s friendship and affection for Lily Evans, the girl Potter fancied and later married. Remus Lupin’s lycanthropy provided the impetus for the Marauders becoming Animagi in order to accompany Lupin around the grounds when he transformed into a werewolf every month. These excursions provided the means for the Marauders to create their signature “Marauder’s Map,” a magical map of Hogwarts castle which showed all the inhabitants and all the known secret passages.
- Harry was told the story of the Marauders by Remus Lupin in the Shrieking Shack when they have Peter Pettigrew cornered as a rat (PA18).
- Minerva McGonagall called James and Sirius "a couple of troublemakers" and "ringleaders of their little gang," meaning the Marauders (PA10).
- Harry was inspired by the idea that his father was a noble stag Animagus, and refers to his own stag Patronus as "Prongs," which was James Potter's nickname in the Marauders (PA18, PA21). He was less impressed after seeing "Snape's Worst Memory" in the Pensieve, as James and the other Marauders ganged up on Snape on the day of their O.W.L. exams (OP28). Harry illegally used Dolores Umbridge's fireplace at Hogwarts to contact Sirius and Lupin at Grimmauld Place, asking why they acted as they did, to which Sirius replied "we were sometimes arrogant little berks" while Snape was "this little oddball who was up to his eyes in the Dark Arts" (OP29).
"Marauder" from 15th century French for "rascal" or mischief-maker. "Marauders" status often ascribed to groups such as pirates or Vikings raiding a coastline to fight or steal a treasure. "Marauding" often denotes sinister motives - "going from one place to another killing or using violence, stealing, and destroying" via the Cambridge Dictionary. "Going about in search of things to steal or people to attack" via Oxford Dictionary.
For years, fans debated whether the term "Marauders" was actually used by James, Sirius, Remus, and Peter, or whether they simply used that word as the title of the map. The fact that the name of the map used the term Marauder in the singular suggested that it didn't refer to a group. However, in answer to a question posed by Steve VanderArk of the Lexicon, Rowling set the record straight when she wrote on her original website:
James, Sirius, Remus and Peter dubbed themselves ‘marauders’, hence the way they titled the map (JKR).