The History of Hendricks County (Chicago: Interstate Publishing, 1885)--Center Township, page 518
Martin Gregg, a retired farmer of Danville, Ind., was born in Grayson County, Va., Feb. 14, 1811. He is the fourth of six sons of John and Elizabeth (Dickenson) Gregg. His father having died when he was only four years old, he went with his mother to Patrick County, Va., where he lived until his eighteenth year. He then came to Indiana alone and lived in Centerville, Wayne County, until 1843 when he came to Hendricks County and purchased a farm near Danville, which is now the county poor farm. He sold his farm in 1863 and retired from the business. In 1864 he was elected one of the commissioners of Hendricks County, which position he held by re-election for fourteen years, and during his term of service the court-house, county jail and county poor house were built and he was chosen by the board to superintend the work. Jan. 24, 1839, he married Mary J. Wortman, daughter of John and Elizabeth (Medaris) Wortman, of Wayne County, Ind. She was born in Hamilton County, Ohio, Feb. 3, 1816, and when eleven years of age she came to Centerville Ind., where she lived till her marriage. They have three children living--Martha, wife of Henry Curtis, of Danville; Mary, wife of S.R. Holt, of Indianapolis, and Emma, still at home. Those deceased are--Sallie, wife of E.D. Nichols, died Feb.30, 1880, aged thirty-six years, and Henry, aged thirteen, died Feb. 18, 1862. Mr. Gregg is politically a Republican, but was originally a Whig. His wife is a member of the Methodist Episcopal Church.