"I figured what a wonderful way to tell a story," Rinaldi said in a telephone interview from her home in Somerville, N.J.
The book, "Mine Eyes Have Seen," hit bookstores in February and Rinaldi will be signing copies during an April 25 visit to Hagerstown.
Rinaldi might never have latched onto Annie's story if not for two people at the Washington County Free Library.
Library Director Mary C. Baykan convinced Rinaldi that she should visit the area to experience its rich history.
Baykan and John Frye, curator of the Western Maryland Room, took Rinaldi on a historical tour of the county. That was when Rinaldi learned about the John Brown Farm for the first time.
Although the farmhouse museum was closed, the tour group peered through the windows and Rinaldi was inspired.
"We're very excited the library played a role. I think it's just a great coup for Hagerstown," Baykan said.
Rinaldi is using another local Civil War story as the backdrop of a novel to be published next year, she said.
On July 6, 1864, Hagerstown was raided by 1,500 Confederate troops who demanded a ransom in retaliation for Union destruction of farms, feed for livestock and cattle.
Three local banks and the Hagerstown City Council produced the money to save the town from being burned while citizens and businesses surrendered pants, shirts, hats and shoes to the Rebels.
Unlike the Annie Brown story, this one will be told through the eyes of two fictional teenagers, Rinaldi said.
At one time, Rinaldi had also considered writing about Mary Titcomb, a Washington County woman who founded the first bookmobile, Baykan said.
Rinaldi, of Somerville, N.J., has built a career on telling history from the perspective of ordinary teenagers.
She has written six ALA Best Books for Young Adults, including "In My Father's House" and "Wolf by the Ears," winner of the 1994 Pacific Northwest Library Association Young Reader's Choice Award, Senior Division, and one of the 100 "Best of the Best" ALA Best Books for Young Adults of the last 25 years.
"I look for the things that relate to every day and how politics and war and chaos affect the people," Rinaldi said. "The behind-the-scenes stuff is what really interests me."
While the innermost feelings of her characters are fictional, the historical events they take part in are true to fact, she said.
Frye agreed that "Mine Eyes Have Seen" was historically accurate.
"I read the whole thing and I don't read fiction," he said.
Rinaldi thoroughly researches all of her subjects.
Her interest in history was sparked by her son, Ron, who took her to Revolutionary War re-enactments held during Bicentennial celebrations in 1976.
She has been writing novels since 1980.
She wrote a general interest column three times a week for a Trenton, N.J., newspaper from 1970 to 1991.
Fans can meet Rinaldi on April 25. The Women's Club on South Prospect Street is hosting a tea from 1 to 3 p.m., Baykan said.
Tickets, being sold at the library and the women's club, are $5 for adults and $3 for students. Proceeds will benefit the library.