John C. Morgan was born on July 20, 1817, in Pennsylvania. He married Mary Catherine Weimer, and they had at least seven children: Laura, born on July 30, 1845; Samuel, born around 1847; Joseph, born on January 12, 1850; Roxanna, born around 1854; Charles, born around 1856; Eugene, born around 1859; and Richard, born on July 12, 1862. They lived in Shamokin, Pennsylvania, and he worked as a merchant. They moved to Sunbury, Pennsylvania, in the 1850s, and by 1860, he owned $5,000 of real estate and $2,000 of personal property. He later worked as a linseed oil manufacturer and an insurance agent.
He supported the Democratic Party, and he helped organize a “Democratic Union Club” in Sunbury in August 1861. According to a local writer, they “showed a determination to rally to the support of those good old Constitutional principles which have so long preserved the Union and enhanced the best interests of the people.” He ran unsuccessfully for sheriff in 1872. He ran again in 1882, and this time he was “elected by a comparatively large majority.” As one writer observed, he “had his ups and downs, but through all he kept an unsullied reputation for honesty and integrity.” His wife died on December 12, 1885, and he passed away in Sunbury on July 28, 1887.