Felix Constantin Alexander Johann Nepomuk Prinz zu Salm-Salm was born at Schloss Anholt in Westphalia on the 25th of December 1828 as the youngest son of Fürst Florentin zu Salm-Salm. On the 2nd of April 1846 he entered the Prussian army as a Second lieutenant of the Garde-Kürassierregiment in Berlin shortly followed by his transfer to the 11th hussar regiment at Münster on the 18th of November 1847. With this regiment he took part in the Prussian-Danish war in 1849. During the battle near Aarhuus on the 18th of May 1849 he thoughtlessly left his post as an Ordonannzofficier, took some hussars with him and attacked a much larger Danish dragoon unit against his orders. This careless action was perhaps heroic but ultimately stupid and Prinz zu Salm-Salm was seriously wounded and captured by the enemy. After his recovery he was transferred to the Garde-Husarenregiment. The good name of his family saved him from greater problems but it was obvious that this action would slow down his career for a long time and so he left the Prussian army on the 8th of June 1854. Felix Prinz zu Salm-Salm now entered the Austrian army as an Unterlieutenant 1st class, soon followed by his promotion to Oberleutnant in ulan regiment number 1. With this regiment he took part on the Franco-Austrian war in northern Italy in 1859 but was unable to distinguish himself there. Another problem, typical for the very low paid young officers of this time, emerged in a particularly harmful way. It was a well known fact that nearly every young officer had many debts, often from the beloved card playing between them and it was also well known that Kaiser Franz Joseph, leading a very frugal life himself, frowned on this activity and gave no sympathy to officers who succumbed to this problem. Prinz Salm-Salm a typical young man from an excellent and very rich family did have the typical problem - he was too thoughtless and didn't know when to stop and soon his debts grew enormous, with no chance to hide them anymore. At the end all came as presumed, he was thrown out of the Austrian army because his "private life was not fitting for an Austrian officer" in 1861 and his father had to calm down his creditors. As a common routine in the 19th century the "black sheep" of good families were sent overseas and so his father bought him a ticket to the USA.
When he arrived in the USA, the Civil War had just began and Prinz Salm-Salm immediately joined the Union Army as chief of the general staff of the German division Blenker. On the 30th of August 1862 he married the charming and ambitious Agnes Le Clerq, the daughter of a Canadian Colonel, who opened for him the doors to important military circles. Soon he entered the senior ranks, and was at first the commander of the 8th, later of the 68th New York infantry regiment and commanded at last a brigade as a Colonel. At the end of the Civil War he was for a short time Military and Civilian Governor of North Georgia but peacetime life was not what this ambitious couple desired and so they traveled to Mexico in the summer 1866. For a man of his reputations it was easy to contact Kaiser Maximilian and offered him his services. Kaiser Maximilian made him a Colonel of the Mexican National Army and appointed him as his 1st Flügeladjutant. In this capacity he was one of the few Europeans who followed Kaiser Maximilian to Querétaro in his last headquarters. During the siege of Querétaro Prinz Salm-Salm found many occasions to distinguish himself in battle. For instance as an interim commander of the Jäger unit he conducted an heroic counter attack on the 13th of March capturing an artillery gun and several republican soldiers including an officer. At the end he was, besides the minister of war and the civilian secretary of Kaiser Maximilian, Jóse Luis Blasio, the only person imprisoned at the convent Santa Brigida with the Emperor who did not hold generals' rank. On the 21st of October 1867 the famous photographer Aubert received permission to take pictures of all imprisoned generals there and, knowing that they were in poor condition mainly in torn civilian clothes, took a Mexican Generals' dress uniform with decorations (from a very fat General) with him to give them a better look on the photos. So all of them wore the same uniform on these photos which was the beginning of the often published legend (the photo was also used as basis for a lithography published in Germany) that Felix Prinz zu Salm-Salm had become a Mexican General! Similar to all captured generals Prinz Salm-Salm was condemned to death but after the great international reaction after the shooting of Kaiser Maximilian and his two generals all judgments were changed into terms of imprisonment of between 10 and 2 years - Prinz Salm-Salm was sent to prison for 7 years at the fortress Ulúa. His wife, who traveled to Querétaro before and then to Mexico City, tried everything she could to liberate him and finally his punishment was commuted into lifelong expulsion.
Back in Europe in November 1868 he again tried to obtain an officers' appointment with the Austro-Hungarian army but this was refused in consequence of his personal file of 1860/61 and so he again entered the Prussian army as Major in the 4th Garde-Grenadier-Regiment on the 10th of December 1868. When the Franco-German war started in 1870 he was in the same regiment as the commander of the Füsilier-Bataillon. During the battle of Gravelotte-St.Privat on the 18th of August 1870 Major Felix Prinz zu Salm-Salm received such serious wounds that he died in the evening of this day in hospital.
By the way, Felix Prinz zu Salm-Salm published a book about his Mexican adventures "Queretaro. Blätter aus meinem Tagebuch in Mexiko" (Stuttgart 1868) and also his wife Agnes Prinzessin zu Salm-Salm published her memories in the 3 volume book "Zehn Jahre aus meinem Leben 1862-1872" (Stuttgart 1875). She married again in 1876, a Charles Heheage and died on the 20th of December 1912 at Bonn.