Born at Eichtersheim (now Angelbachtal in Baden-Württemberg), the son of a revenue official, he studied law at the University of Heidelberg with the intention of becoming a lawyer.

[1] He abandoned the legal profession on being elected to the Second Chamber of Baden in 1842, and at once began to take part in the opposition against the government, which assumed a more and more openly radical character.

[1] In early 1845 the political issue of the incorporation of Schleswig and Holstein with Denmark arose in the public eye, with a particular interest to democratically minded politicians who favored unity of all the German states as a core of their programme.

On March 9 his friend and liberal compatriot Adolf Sander died suddenly of a lung disease, marking the beginning an ever increasing tone of bitterness by Hecker toward the government.

Later that year he and Johann Adam von Itzstein conducted a campaign of democracy, one result of which was his expulsion from Prussia on the occasion of a journey to Stettin, which had the effect of adding to his popularity.

[2][3] In 1847 he was temporarily occupied with ideas of emigration, and with this object made a journey to Algiers, but returned to Baden and resumed his former position as the radical champion of popular rights, later becoming president of the Volksverein, where he was destined to fall still further under the influence of the agitator Gustav von Struve.

In conjunction with Struve he drew up the radical programme carried at the great Liberal meeting held at Offenburg on September 12, 1847 (entitled Thirteen Claims put forward by the People of Baden).

The proof lies in the new Offenburg demands of March 19, and in the resolution moved by Hecker in the preliminary Frankfurt Parliament that Germany should be declared a republic.

On being refused admission to the Frankfurt Parliament, though twice elected to represent Thiengen, Hecker resolved in September 1848 to emigrate to North America like many other Forty-Eighters and bought a farm near Belleville, Illinois.

[4] When the Illinois Republican Party was organized at a convention in 1856, German-American Forty-Eighters were everywhere conspicuous in the proceedings; Hecker and Abraham Lincoln were selected to be the two electors-at-large if John Frémont were to win the state (which he did not).

[5] The Republicans attracted a wide array of political perspectives, with often strongly divergent views except for their opposition to slavery, and the interests of the immigrant Forty-Eighters was in sharp conflict with those of the nativist Know Nothings.

The 24th Illinois was the first unit mobilized from Chicago, and was made up of German, Hungarian, Czech and Slovak immigrants, mostly Forty-Eighters.

In the early days of the war, the 24th Illinois primarily was assigned to garrison and other rear echelon duties in the western theaters.

Under the conditions of dreary guard duty, and not being professional soldiers, morale and discipline faltered, and Hecker resigned his command on December 23, 1861.