He was appointed a professor of foreign languages at Dalhousie College in Halifax in 1855, as he spoke (at least) English, Hungarian, German, Spanish, French, and Italian.

Initially divided into 11 companies of men from Germany, Hungary, Switzerland, Italy, France, Spain and Portugal, it would ultimately host 11 different nationalities.

Attached into the 1st Brigade (Col. Louis Blenker) of the 5th Division (Col. Dixon S. Miles) it was only slightly engaged at the First Battle of Bull Run.

Stationed in Alexandria, the ill feelings of the multi-ethnic regiment turned into violence and sparked several mutinies - all of those were quelled in D'Utassy's presence.

At the same time rumors were spread that D'Utassy was an impostor who forged his military records, and in reality an Austrian Jew by the name of Frederick Strasser; but he never officially denounced them.

At the same time D'Utassy was accused of fraudulently drawing additional rations, but he proved the correctness of his action and the charge was neutralized.

At the same time the division was assigned from Sumner's II Corps to Maj. Gen. John C. Frémont's Mountain Department and joined his forces on May 11, taking part in the engagement near Strasburg.

During July and August it encamped at Middletown, Virginia; and D'Utassy, now free from the ethnical struggles with his commanders, managed to get the appreciation and admiration of his fellow American officers.

He, like Gen. White and the other brigade commanders, was arrested by order of the Adjutant-General and had to testify on the court-martial about the conduct at Harper's Ferry under presidency of Gen. David Hunter.

They officially exchanged in November and returned to Washington, when Colonel D'Utassy was assigned to command the 1st Brigade of the provisional division of Maj. Gen. Silas Casey at Union Mills, Maryland.

A court-martial convened on April 2 under presidency of Maj. Gen. Ethan A. Hitchcock, and D'Utassy was accused of 3 charges with 25 individual specifications - on which he pleaded not guilty.

More importantly, he was found guilty of "Conduct prejudicial to good order and military discipline" by unlawfully opening post, selling the position of Major in his regiment to a fellow officer, forging muster rolls, and forging accounts to fraudulently receive several thousand dollars.

D'Utassy was sentenced: To forfeit all pay and allowances now due and that may become due to him; To be cashiered; To be confined at hard labor for the period of one year at such place as the Secretary of War shall direct; To be disqualified from holding any office of trust honor, or employment in the service of the United States, and the crime, name, and punishment of the delinquent to be published in at least three of the public papers of the State of New York.

Arriving at the prison with a great media presence it is alleged that, when asking for a better treatment, he told a guard, "I speak twelve languages!"