A native of Pensacola, Florida, Senac married in Mobile, Alabama, and moved his family to Key West just prior to the American Civil War.

[3] Senac was related by marriage to Confederate States Navy secretary Stephen Mallory and Marine Corps 2nd lieutenant John L. Rapier.

In a letter to the Confederate agent James Dunwoody Bulloch, Mallory describes him thus: "He speaks French with purity and elegance, Spanish also, possesses fine business capacity, and is a gentleman of ripe judgement and rare merit".

In 1856 he was appointed purser in the United States Navy and moved his family to Washington, D.C. His daughter Ruby was a student at Georgetown Visitation school for girls.

On September 15, 1862, Senac was summoned to Richmond, Virginia, in front of a Congressional Committee to explain the reasons for the loss of the two Confederate ironclads.

Having reached London, the family ultimately settled in Paris as Senac traveled to England and around Europe trying to secure clothing, shoes, and weapons for the Confederacy.

On February 28, 1865, as Confederate agents in Europe were slowly preparing to make their way back to the Confederacy, Senac received orders from Richmond to stay in Paris.