John Leake Marling was born on December 22, 1825 in Nashville, Tennessee, and was the son of Samuel and Charlotte Clara (Leake) Marling. Under the pen-name of "Clara" his mother wrote popular sentimental verses, and Marling inherited and to some extent practised his mother's gift.
Beginning his career in a printing office, Marling overcame his lack of a systematic education by reading in leisure moments, and though without wealth or family prestige won his way into public life by a precocious exercise of his talent for political writing. He studied law in the office of A. O. P. Nicholson and Russell Houston and was admitted to the bar, but did not practise.
In July 1850 he became editor and part-owner of the Nashville Daily Gazette, and thus, in the heat of the controversy over the territorial expansion of slavery, entered upon his short, but stormy and brilliant, journalistic career. On taking over the Gazette he announced that he would conduct it as an "independent" paper, avoiding partisan quarrels, but he speedily became embroiled in the excitement that attended upon the meetings of the Southern convention in Nashville in 1850. During the second session of the convention he uncompromisingly denounced the secessionist policies it expressed, to such effect that there was an attempt to exclude him from its sessions. In his editorial opposition he undoubtedly reflected a strong element of Tennessee opinion. In September 1851, leaving the Gazette, Marling became part-owner and editor of the Nashville Daily Union, a prominent Democratic paper. The young editor soon was hotly involved in the presidential campaign of 1852, strongly advocating the candidacy of Pierce against a powerful Whig opposition, locally centered in the Republican Banner, edited by Felix K. Zollicoffer. On August 20, 1852, at the height of the campaign, Marling topped a series of attacks on the Banner by openly charging its editor with misrepresentation of Pierce's Southern sympathies, and in effect giving Zollicoffer the lie. Zollicoffer's answer was to call Marling out for personal satisfaction, which Marling immediately tendered. That morning the two editors met on the street in front of the Union office and, with little preliminary, exchanged several shots. Marling was seriously wounded and was unable to resume his duties until the campaign was over. It was thought, even by Zollicoffer's friends, that the difficulty was less personal than political and that Marling, who was known as a brave man and a crack pistol shot, had been egged on by Democratic partisans who wished to put Zollicoffer, a strong political opponent, out of the way. At any rate the difficulty between the two was later composed. Marling continued his connection with the Union through its consolidation with the American in 1853. Less than two years later he became seriously ill and returned to Nashville, on leave, in May 1856, to die there of tuberculosis within a few months.
At seventeen he joined the Baptist church.
On May 16, 1850, he was married to Mary E. March of Nashville.
