Thomas D. Gregg was born during the latter part of the nineteenth century, but his early life is lost to the written record of Marion County and Indianapolis. He seems to have appeared in this city in the early 1820s, as a teacher in one and another of the schools that existed. He was among the teachers when the Marion County Seminary opened in 1834, a school for boys that was privately operated. He became head of that school two years later, then started his own at the corner of Delaware and Market shortly afterwards.

He was described by his contemporaries as a stern but excellent teacher. There is no evidence that he was married, nor that he was active in the affairs of the town. He apparently left here in 1848, though it is not clear whether or not he was a continuous resident here until that time.  Whether through inheritance or purchase, he acquired considerable real estate in the vicinity of Adel, Iowa, and made several trips to that area to look after his property. It is doubtful if he ever lived in that state, however.

Gregg died in King William County, Virginia, on December 17, 1876. Two will soon made their appearance, one in favor of the Indianapolis schools, the other granting a sum of money to Dallas County, Iowa. There was a jury trial at King William, Virginia, in June of 1878, but a settlement was made out of court.

Under terms of the settlement, the Indianapolis schools received a sum of money, and the Iowa county received a sum. The Gregg Fund, in Indianapolis, is used to provide training in needed areas for elementary teachers. There is presently more than $50,000 in the fund, administered by the Board of School Commissioners.