During this year (1863) he made a number of speeches in favor of President Lincoln's policy to re-establish a loyal State government in Louisiana, and in a speech at Lyceum Hall, New Orleans, in November, 1863, he declared for the abolition of slavery in the whole State.
In January, 1864, he took charge, as owner and editor, of the New Orleans Daily True Delta, in which he advocated emancipation, being the first paper ever owned by a Louisianian to do so. On the reconstruction of the State government on a loyal basis, February, 1864, Mr. Hahn was elected the first free-State governor, and was inducted into office in March following. In the same month President Lincoln invested him with the additional powers of a military governor.
A reconstruction constitution for the State having been declared adopted, a legislature was elected thereunder, which in January, 1865, elected Governor Hahn to the United States Senate for six years. In consequence of this election he resigned the office of governor, but never pressed his claim to a seat in the Senate.
On the 4th of July, 1865, he made a speech at the emancipation celebration in Washington, which was widely circulated.
A few months later he made a speech before the Equal Suffrage Association of Washington, which also obtained wide circulation.
In 1867 he became editor and manager of the New Orleans Daily Republican, and continued with eminent success in that position until 1871. During this time he received the appointment of administrator of the Charity Hospital of New Orleans. On quitting journalistic life he retired to his plantation in Saint Charles Parish. Here he laid out and built the pretty and thriving village of Hahnville.
He was made a school director of Saint Charles Parish, and repeatedly elected to represent the parish in the legislature of the State. In 1872 he served as president of the Louisiana State educational convention during its three days' session.
While in the legislature he served as chairman of the committee on the judiciary and a short time as speaker.
In 1876 he was appointed State registrar of voters; in 1878 he was unanimously elected police juror for his parish, and in June, 1878,
