Born in Washington Township, Southard graduated from Cornell University in 1874. He was admitted to the bar in 1877 and began practicing law in Toledo where he was appointed assistant prosecuting attorney of Lucas County in 1882. He served in that office for six years.

 

In 1895, he was elected as a Republican to the Fifty-fourth Congress and to the five succeeding Congresses, serving until 1907. He served as chairman of the Committee on Coinage, Weights, and Measures. After an unsuccessful reelection bid in 1906, he returned to his law practice in Toledo.