He was a Confederate soldier during the Civil War.

1860 Virginia, Floyd County, p. 159 (taken 14 Aug 1860)
dwelling1150, family 1073
Alfred O’Neal, age 50, male, farmer, real estate $2500, personal $1229, born Tennessee
p. 160
Francis O’Neal, age 52, female, born Virginia
Isaac W. O’Neal, age 22, male, miller, born [blank]
Benj. B. ———-, age 19, male, farmer, born [blank], attended school
Leander T. ——, age 14, male, born [blank], attended school
Loeza W. ——-, age 12, female, born [blank], attended school

1870 Virginia, Floyd County, Burks Fork & Madison Valley Townships, p. 51 (taken 8 Sept 1870)
dwelling 358, family 337
O’Neal, Isaac W., age 32, male, white, wool carder, personal $460, born Virginia
———, Nancy, age 24, female, white, keeping house, born Virginia
———, Maggie E., age 1, female, white, born Virginia

1880 Virginia, Floyd County, Burks Fork Magisterial District, E.D. 26, page 1A, stamped page 277 (taken 1 Jun 1880)
dwelling 7, family 7
Oneal, I. W., white, male, age 42, head, married, woll carder, born Virginia, [parents blank]
———, Nancy, white, female, age 34, wife, married, keeping house, born Virginia, parents born Virginia
———, O. C., white, male, age 9, son, single, has fits, mark under idiotic and maimed category, born Virginia, parents born Virginia
———, Arthur L., white, male, age 7, son, single, attended school, born Virginia, parents born Virginia
———, Benjamin F., white, male, age 6, son, single, attended school, born Virginia, parents born Virginia
———, John ?., white, male, age 4, son, single, born Virginia, parents born Virginia
———, Lewis C., white, male, age 2, son, single, born Virginia, parents born Virginia
———, Maggie E., white, female, age 10, daughter, single, born Virginia, parents born Virginia
———, Lyetetia N., white, female, age 1, daughter, single, born Virginia, parents born Virginia

1900 Ohio, Preble County, Washington Township, E.D. 113, sheet 12A, stamped page 211 (taken 20-21 June 1900)
dwelling 253, family 254
O’Neal, Isaac W., head, white, male, Oct 1837, age 62, married for 32 years, born Virginia, father born North Carolina, mother born Virginia, farmer
———, Nancy, wife, white, female, Dec, 1845, age 54, married for 32 years, mother of 12 children, 9 living, born Virginia, parents born Virginia
———, Ora E., daughter, white, female, Mar 1881, age 19, single, born Virginia, parents born Virginia
———, Judson, son, white, male, Jan 1884, age 16, single, born Virginia, parents born Virginia
———, Hallie G., daughter, white, female, Oct 1890, age 9, single, born Virginia, parents born Virginia
———, Blanche, daughter, white, female, Jan 1900, age 4/12, single, born Virginia, parents born Virginia
—————————————————deceased