He is best known for his best-selling novel Forrest Gump (1986), which became a 1990s cultural phenomenon after being adapted as the film of the same name directed by Robert Zemeckis and starring Tom Hanks.

After the film was released, gaining a high box office and winning numerous awards, Groom's novel sold more than one million copies worldwide.

His book Conversations with the Enemy (1982) follows an American soldier who escapes from a POW camp in Vietnam and takes a plane back to the United States.

The film received six Academy Awards and numerous others; its popularity propelled the novel to best-seller status, and it sold 1.7 million copies worldwide.

He eventually settled with Paramount in 1995 in an agreement that included a seven-figure sum for the film rights to Gump and Co., plus a percentage of the gross profits.

Groom describes how Brigadier General Stephen W. Kearny's quest for westward adventure coincided with the expansionist desires of U.S. President James K. Polk.

Groom weaves into Kearny's March mountain man Kit Carson, Brigham Young and his Mormon followers, and members of the Donner party.

[10] At the time of his death in 2020, Groom was waiting for publication of The Patriots, his biography of American leaders John Adams, Alexander Hamilton, and Thomas Jefferson.