John Brown is important not only to his home state of Kentucky but also to his country. James Madison, the 4th President of the United States said of Brown, I owe it to Mr. Brown with whom I was in intimate friendship when we were associated in public life, to observe that I always regarded him, whilst steadily attentive to the interests of his constituents, as duly impressed with the importance of the Union, and anxious for its prosperity. - Excerpt from letter to Mann Butler, Esq. from James Madison, October 11, 1834, From Collins, History of Kentucky, Volume 1.1966.)

In 1805, after twenty years of public service, Brown returned to Kentucky and became a very active member of the Frankfort Community. He purchased a ferry that crossed the Kentucky River and served as the Sheriff of Franklin County. Brown was a founding member of the Frankfort Water Company and the Bank of Kentucky. He also managed hundreds of acres of property in Central Kentucky and 20,000 acres near Chillicothe, Ohio.

In 1812 John Brown was appointed by the legislature to oversee the construction of a public house of worship on the public square of Frankfort. Brown served on the board that oversaw the brick Capitol building and the limestone one that replaced it, now known as the Old State Capitol. In 1836, John Brown presided over the organizational meeting of the Kentucky Historical Society.

Brown died in 1837, he was 79 years old. At the time of his death he had the distinction of being the last living member of the Continental Congress.