It is author Jack Todd’s conceit that “even in fiction there has to be truth.”

Honoring those words, his first fictional novel, “Sun Going Down” (Simon & Schuster, 2008), arguably took a lifetime of truth-seeking. When he arrives at Park City Library’s Visiting Author Series this Wednesday, it will have been after decades of listening to family tales, and more decades of reading and hunting down the facts by touring American landmarks and historical by foot.

“Sun Going Down,” an epic tale of a family by the name of Paint, elaborates the legends and lore of Todd’s ancestors beginning 150 years ago on the Western frontier.

The outline is based on what actually happened: A man is on the river during the Civil War running a boat with a freed slave and gets caught in the crossfire. Later he moves to South Dakota, tries various ventures, and has a son who becomes a very wealthy rancher. That son, Eli, ends up having a daughter, who is based on Todd’s grandmother, Velma, an important figure whose bold, vagabond life is captured within the novel’s covers.

“A lot of this was oral history I got from my father, mother, aunts and uncles, all those people when I was young who told me stories directly,” he says.

Velma’s story, which is much defined by Eli’s disgust over her consummated relationship with a ranch hand, is what Todd feels distinguishes “Sun Going Down” from other historical fiction works.

“It’s an unusual story the scope of it,” says Todd. “But it wasn’t until I focused on the star-crossed relationship between Eli and Velma when he kicks her off the ranch, her subsequent life, his late effort to reconcile that I was finally ready to sit down and write You can’t just write about incident after incident after incident. That really doesn’t add up to a novel.”

In part, the storyline was revealed in an unexpected wealth of records. Nearly 25 years ago, while working as a Canadian sports reporter, received a package from his mother full of further details about their family’s past: a memoir written by his great aunt and 50 years of journal entries left by a great-great-uncle Eb Jones, the son of one of the first pioneers in South Dakota and a scout for the U.S. Cavalry at the time of the Wounded Knee massacre in 1890.

It was then that Todd fully recognized the value in his family’s connections tovarious historical plots and pivotal moments in United States history. They had participated in the Gold Rush in 1849, traveled by Mississippi steamboat, and later faced hard luck during the Great Depression.

“I always think you can tell the story of the general better through the specifics than just reciting the dates and facts,” he says. “What I hope to do is illuminate American history by telling the story of a particular family.”

And he aims to recount the past with precision. “If I said a river is five miles south of a rock, I wanted it to be there,” Todd explains.

To expand the sketchy paragraphs and hand-me-down memories, Todd says he has spent the better part of the last decade reading and re-reading books and visiting the sites where his novel takes place. This research and the memories of a young childhood in the rural outskirts of Nebraska, helped him to get inside the period he was writing about.

“Before I was six or seven, we were all still living with a coal-fired stove and no telephone and an outhouse,” he reveals, “so I have a bit of an immediate sense of what it’s like to live that way; to be self-reliant.”

Beyond “Sun Going Down,” Todd says he has already contracted with Simon & Schuster for two more novels based on his family history. The next volume, “Fire on the Water,” covers the story of his mother’s half-brother Bobby who became a gunner on the Tennesee Battleship during World War II. The third, “The Rain Came Down,” will follow the Paint family into the 1950s and 1960s.

“It will be a trilogy when I’m done and then I’ll do something else,” Todd predicts. “I hope to be around long enough to write 10 or 12 of these things.”

Attend a reading of “Sun Going Down”

What: A reading of “Sun Going Down” (Simon & Schuster, 2008) by Jack Todd, presented by the Park City Library Author Series

When: Wednesday, May 21, at 7 p.m.

Who: Jack Todd, the author of the memoir, “Desertion: In the Time of Vietnam,” which won the Mavis Gallant Prize for Non-Fiction, the Quebec Writer’s Federation First Book Prize.

Where: At the Park City Library, 1255 Park Ave.

For more information: visit simonsays.com.

Up next: On June 5, the Park City Library Visiting Author Series plans to welcome Mike Farrell of the television show “M*A*S*H” who will read from his book, “Just Call Me Mike: A Journey to Actor and Activist.”