James married Sarah Wood 10 Oct 1822 at Clermont County, Ohio and together were parents to:

- Absalom Buchanan
- Elizabeth Buchanan
- Enoch Buchanan
- Catharine Buchanan
- David Buchanan
- William Wood Buchanan

James was a veteran of the Black Hawk War, he was a Sergeant in Col Mayo's 1st Regiment 2nd Brigade. The following excerpt from The history of Edgar County, Illinois (1879):

"In 1882, the Indians concentrated for a last struggle in defense of their
hunting-grounds, under the renowned chief, Black Hawk. The notes of war
reached this sparsely-settled district, and more than three hundred men from this
county responded to the Governor's call for troops. Milton K. Alexander, a
merchant of Paris, had been commissioned Colonel of the Nineteenth' Regiment
of Illinois Militia. In 1880, he was appointed Aide-de-Camp to Gov. Reynolds,
and accompanied him the next year to Rock Island, on business connected with
the threatened outbreak. In 1832, he was elected and commissioned Brigadier
General of the Second Brigade of Illinois Volunteers, and J. M. Blackburn,
still living, and residing in Stratton Township, was commissioned Colonel of
the regiment formed in this county, and which composed a part of Gen. Alexander's brigade. Following, we give the names of the officers and privates of
the regiment, so far as could be obtained : J. M. Blackburn, Colonel ; William
Wyatt, Lieutenant Colonel ; Stephen J. Shellady, Adjutant ; Leonard Parker,
Quartermaster ; Drs. Ferris and Huff, Surgeons. In forming the regiment,
the companies composing it drew lots for precedence, and Mayo's obtained the
post of honor. It was originally officered as follows : Jonathan Mayo, Cap-
tain : Edward Y. Russell, First Lieutenant; William Wyatt, Second Lieu-
tenant ; Leonard Parker, Orderly Sergeant. Upon the formation of the reg-
iment, Wyatt and Parker were promoted, as above, and John S. McConkey
was elected Lieutenant, in place of Wyatt, and James Buchanan, Orderly Ser-
geant, in the place of Parker."