After the Russian Empire lost the Crimean War and was weakened economically and politically, an unrest started on the lands of the former Polish–Lithuanian Commonwealth.

Being under the persecution of the Russian government he escaped to Italy, where he taught the war fortification at the Military School in Genoa.

Only with the help of the bribes given to Russian officials and selling of family estates, he managed to escape the death penalty and was sent to a 12-year Katorga in Siberia.

After graduating with a degree in civil engineering, Mineyko led construction of railways, bridges and channels in Bulgaria, Turkey and Greece.

Mineyko then worked for 20 years in the service of the Ottoman Empire, building roads, railways, and bridges in Bulgaria, Thrace, Thessaly, and Epirus.

[4] In 1878 he made a sensational archaeological discovery, when his expedition found traces of the major ancient sanctuary of Zeus in Dodona.

He also was a member of the executive committee for Crete in 1896, and in 1897 he was head of the topographic section of the General Staff of the Greek Army.

He wrote letters for Polish periodicals in Kraków and Lwow for many years, presenting the problems of Greek politics and ethnic questions from a pro-Hellenic point of view.

During the First Balkan War, in 1913, his strategic plans became crucial in achieving the decisive Greek victory at the battle of Bizani, which led to the capture of Ioannina and Epirus by Greece.

As an engineer and head of the cartographic service of the Greek General Staff, and with his prior knowledge of the region, he prepared a plan for the outflanking movement which led to the taking of the strongly fortified Turkish position of "Bizani", which sealed entry to the Ioannina Valley.

In November 1919, the affair became famous when, during the trial of General Staff Officers, the Athenian journals "Patris" and "Nea Ellas" revealed Mineyko’s contribution.

One of their daughters, Sophia, married Georgios Papandreou, the Governor of Chios who later served three terms as Prime Minister of Greece (1944–1945, 1963, 1964–1965).

[10][11] Mineyko could speak Polish, Lithuanian, Russian, French, Turkish, and Greek, was an excellent horseman and hunter.

After the end of the First Balkan War, he was also conferred upon the highest award of Greece, the Gold Cross of the Order of the Redeemer (1913).