Wilson Caldwell (1845-1921) was just 18 and living in Posey township, Fayette County, Indiana with his farming family when he enlisted on July 10, 1863 in the 104th Indiana Infantry, Company K. On this map, Posey is at top left of the county.
Wilson and his fellow minute men served just eight days because they were enlisted specifically for short-term emergency service, not for regular military service.
From Union Army, vol. 3, p. 174, a description of his unit's history in the context of other units formed at the same time:
One Hundred and Fourth Infantry Indiana Minute Men. -Word being received at Indianapolis on the evening of July 8, 1863, that a force of 6,000 cavalry under [Confederate General] Morgan had crossed the Ohio River near Mauckport and was moving on Corydon, a call was issued for citizens to organize for defense. Within 48 hours 65,000 men had tendered their services. From this number regiments 102 to 114 inclusive, and one battalion were organized, the battalion being assigned to the 107th. One Hundred and Fourth Infantry. -Col., James Gavin, Lieut.Col. Jacob S. Buchanan Maj., Martin W. Richardson. This regiment consisted of six companies of minute men and four of the Legion: Six companies were from Decatur County and one each from Fayette, Madison, Marion and Rush Counties. The regiment was organized at Greensburg, July 10, 1863, with 719 rank and file, and moved to Sunman's station, thence to Lawrenceburg, and from there toward Harrison, Ohio. It returned to Greensburg after Morgan's escape and was mustered out July 18, 1863.
Wilson and his fellow minute men helped chase the Confederates but once the local threat was diminished, they were mustered out and returned home. Note: (Confederate General Morgan was captured in Ohio just eight days after the 104th was mustered out.)
Wilson married Annie B. Cassell and after a short period of farming in Posey, he became an agent and salesman, moving the family to the more populous Wayne County, Indiana. He and Annie had three children together.
Sadly, Annie passed away in 1906 but Wilson kept working to support himself and his youngest child. He wrapped up his working life as the manager of an Indianapolis billiards hall, according to the US Census of1920.
Wilson Caldwell died on July 18, 1921, exactly 58 years after being mustered out of his Civil War unit.