His father, Edward A. O'Neal, was a lawyer who became a Confederate States Army officer during the American Civil War.

He played a prominent role in framing the suffrage provisions, adding a poll tax, literacy test (administered subjectively by white officials), and property ownership requirements.

In the runup to the 1908 presidential election, O'Neal made an extensive speaking tour in the West campaigning for William Jennings Bryan.

Among the more important achievements of his administration was the improvement of the convict system, the impetus given to good roads, and the creation of the State Highway Commission.

Special counsels were appointed in both civil and criminal cases where the interests of the public and the State were concerned.

At the Governors' conference meeting in Richmond, Virginia, he delivered an address on the importance of establishing a system for rural credit (including the availability of cooperative credit unions, cooperative land banks, and similar organizations).

Governor O'Neal made the commission system his favored reform and secured its passage by the legislature in 1911.

[3] He was a member of the Knights of Pythias, the Elks, the Presbyterian church, and the Phi Beta Kappa society.