1802 Christopher Hartman built a log cabin about 200 yards south of the present residence of J.K. Hartman (perhaps this one), where he kept the first hotel in Jackson Twp. 
1850 John K Hartman (age 40, born in Ohio) lived in Jackson, Clermont County, Ohio with Elizabeth Hartman (age 37), and Julia A Hartman (age 10). 
1813 On 7 March, Elizabeth Abernathy Hartman was reported born. 
The following report by John Kilby is from the Clermont County Genealogical Society posted at www.rootsweb.ancestry.com/~ohclecgs/newsletter/jackson.html. The last paragraph, mentions Isaac, the father of J.K. Hartman and Christopher Hartman. "Old Timers, The First Settlers of Jackson Township, From the August 4, 1897 Clermont Courier:
What is now known as Jackson Township was first settled in the spring of 1799, by William Hunter, Sr and Robert Dickey, brothers-in-law. Win. Hunter was born in the county of Denegaul, Ireland. While a young man he came to the United States, landing in 1783. He settled in Chautauqua, Franklin County, Pennsylvania, where in 1787, he was married to Polly Dickey. There was born to them there four children, John, Robert, Peggy and Polly. In 1798, accompanied by his family and brother-in-law, Robert Dickey, he came to Ohio. They spent the winter of 1798 and 1799 in the present Williamsburg, then called Lytlestown. The following spring they settled in what is now Jackson Township on a tract of land containing 500 acres purchased by Dickey from Win. Lytle in survey No.353 1. Under the territorial government Win. Hunter and Houten Clark, a scale maker, were appointed the first justices of the peace in Clermont County. Hunter continued to hold the office by election until 1825. Three children were born to Mr. and Mrs. Hunter in Jackson Township, viz: David Patterson, William and Alexander King. David P. Hunter was the first white child born in the township, he was born in 1800. Robert Hunter, the second son, was a soldier, in the war of 1812. They all have passed away. They were a quiet, law-abiding family. I never heard of any one of them being sued or having any litigation in law. They were a family of good, ordinary intelligence, yet never studied the art of being witnesses in law suits. Win. Hunter, Sr. died in 1834, aged 75 years.
Robert Dickey was born in Chambersburg, Pennsylvania,in the year 1757. At the age of 22 he came down the Ohio River to Louisville, from there to Harod's Station, Kentucky.He volunteered under Benjamin Logan and Colonel Bowmanto fight the Indians. A company of them crossed the Ohio at the mouth of the Licking, thence up the Little Miami River to an Indian town called Chillicothe, about two or three miles north of the present town of Xenia. Their object was to surprise the town about daybreak, but a dog belonging to a young Indian Out hunting near the town, espying the soldiers bayed aloud; thus alarmed, the Indians gained their block house. But few shots were fired on either side, but one of these lodged a ball in Dickey's shoulder.
The surprise being spoiled they retreated across the Ohio at the mouth of the Little Miami; thence to Harod's Station. After some few minor scrapes with the Indians Dickey returned to Chambersburg in the following September and had the bullet extracted from his shoulder. He afterwards took part in Hanne's disastrous campaign. His life was full of thrilling back-woods incidents. I remember when in my teens of hearing him tell my father, Isaac Hartman of wounding a bear, old bruin made for him, it taxed his dexterity to reload, with naked ball, in time to receive his bearship. It was so close when he fired the fatal shot that the powder burned the hair on it's head. Robert Dickey was a man of few words, and of the strictest integrity. He never married. He died in April, 1840; aged 83 years. The next family that settled in the township was Christopher Hartman's. They came in 1802. J.K.H."
 J. L. Rockey and R. J. Bancroft, 1795 History of Clermont County, Ohio, with illustrations and biographical sketches of its prominent men and pioneers (Philadelphia: Louis H. Everts & Co, 1880), 547, [HathiTrust].
 US census, 1850, [AncestryImage], [AncestryRecord].
 Find A Grave Memorial 22108534, [FindAGrave].