It's not hard to figure out why the legend of Sybil Ludington and the Danbury raid became so popular in the twentieth century. It's a good story, with an individual protagonist and a beginning, middle, and end. At sixteen, Sybil was young enough for schoolgirls to identify with her. Most important, her tale is one of the few anecdotes from the Revolution that shows an individual woman contributing to an American military victory through physical activity (though not using weapons herself—heaven forbid!). Sybil’s story came to light just as women's suffrage was finally gathering steam, and it served the values of that time and the decades that followed.
We know many other women were active in the Revolutionary movement, but they usually remained in the domestic sphere, worked collectively, and didn't get noticed. (Of course, the same applies to most males. But the exceptional males far outnumber the exceptional females.)
Here's a better documented example of a young woman helping the American forces, a first-person account from the Memoir of Col. Benjamin Tallmadge, published in 1858. In December 1777 Tallmadge (shown here in a portrait based on a sketch by John Trumbull) was a twenty-three-year-old cavalry officer attached to the Continental Army at Valley Forge. His unit received an assignment that called on their ability to travel fast and light:
being informed that a country girl had gone into Philadelphia, with eggs, instructed to obtain some information respecting the enemy, I moved my detachment to Germantown, where they halted, while, with a small detachment, I advanced several miles towards the British lines, and dismounted at a tavern called the Rising Sun, in full view of their out-posts.That was apparently Tallmadge's introduction to the world of intelligence. Eventually that would become a major responsibility for him; as Washington besieged New York, he asked Tallmadge as a Long Islander to run the spy ring inside the city. Tallmadge was extremely circumspect about those activities when he wrote his memoir. Though his other papers include plenty of evidence to confirm his intelligence activities, including a codebook, for his children he wrote only that Gen. Washington “requested me to take charge of a particular part of his private correspondence.”
Very soon I saw a young female coming out from the city, who also came to the same tavern. After we had made ourselves known to each other, and while she was communicating some intelligence to me, I was informed that the British light horse were advancing. Stepping to the door, I saw them at full speed chasing in my patrols, one of whom they took.
I immediately mounted, when I found the young damsel close by my side, entreating that I would protect her. Having not a moment to reflect, I desired her to mount behind me, and in this way I brought her off more than three miles up to Germantown, where she dismounted.
During the whole ride, although there was considerable firing of pistols, and not a little wheeling and charging, she remained unmoved, and never once complained of fear after she mounted my horse.
I was delighted with this transaction, and received many compliments from those who became acquainted with it.
The Rising Sun tavern between Philadelphia and Germantown seems to have been a regular rendezvous point for exchanging intelligence in the winter of 1777-78. Commissary of prisoners Elias Boudinot wrote in his journal about rendezvousing there with "a little poor looking insignificant Old Woman" who passed him important news hidden in "a dirty old needle book, with various small pockets in it." (That could have been Lydia Darragh, whose daughter Ann later told much more romantic stories about her mother's spying during that winter. Darragh, born in Ireland in 1729, certainly wasn't a "country girl" or "young damsel," but her daughter certainly wouldn't have depicted her as a "poor looking insignificant Old Woman.")
Who was the brave young woman Tallmadge met south of Germantown? What information did she provide the Continental commanders? I don't know. I don't think anyone does. She was a spy, after all, so she kept her mouth shut. Even Tallmadge, at that stage in his career, probably wasn't privy to all the details. And since we don't know that young woman's name or her mission or the results, we can't make an inspiring "true" story out of her, as people have with Sybil Ludington. Pity.