Stephen Augustus Hurlbut (November 29, 1815 – March 27, 1882) was an attorney and politician, who commanded the U.S. Army of the Gulf in the American Civil War. Afterward, he continued to serve as a politician and also as a diplomat.

Although born and educated in the South, his parents were from the North and his father was a Unitarian minister. After passing the bar, Hurlbut moved at the age of 30 to Illinois to set up a practice. There he married and had a family.

When war broke out, he supported the Union and Republican Party. Hurlbut was present at the Battle of Shiloh and served under General Sherman during the Meridian Expedition.

After the war, he returned to politics. He served in various capacities, being appointed as Minister to Colombia and elected as a U.S. congressman from Illinois.

Hurlbut was born in 1815 in Charleston, South Carolina, to Martin Luther Hurlbut and Lydia Bunce, who were from the North. His father was a Unitarian minister and educator. He had been president of Beaufort College in South Carolina from 1812 to 1814. Hurlbut studied law with James L. Petigru as his mentor, worked for him as a law clerk, and was admitted to the South Carolina Bar in 1837. During the Second Seminole War, he served as adjutant of a South Carolina infantry regiment.

In 1845, Hurlbut moved north to Illinois, a free state. He established a law practice in Belvidere. He started his own family in 1847 after marrying Sophronia R. Stevens; they had two children together.

In 1847, Hurlbut took part in the Illinois constitutional convention as a Whig delegate. He served as a presidential elector for the Whig Party in the 1848 presidential election, and became acquainted with Abraham Lincoln during campaigning for Old Rough and Ready Zachary Taylor.

He was elected to the Illinois House of Representatives in 1859 and re-elected in 1861.