After the outbreak of Lord Dunmore's War in May 1774, Arbuckle both assumed command of a company of Botetourt County militia and served as guide and chief scout for General Andrew Lewis's late summer march to Point Pleasant.
In 1776, Arbuckle built Fort Randolph at Point Pleasant and was in command there the following year when a contingent of newly arrived and undisciplined militia witnessed one of their number killed and scalped by Indians.
This mob overcame their officers' (including Arbuckle's) attempts to maintain order and famously murdered the captive Cornstalk, an event which cast a shadow over the region for decades.
On June 27, returning from the temporary state capital at Staunton with Archer Mathews, the men became trapped in a violent storm near the banks of the Jackson River and Arbuckle was killed by a falling tree.
[2] He was laid to rest where he fell and was survived by his widow (Frances Lawrence Arbuckle Hunter Welch; 1749 – 1834) and six sons (Charles, 1768–1846; John, 1771–1843; James Harvey, 1774–1869; Mathew Jr, 1778–1851; Thomas, 1780–1838; and Samuel, 1782–1831).