The Glinsky family claims descent from Orthodox Hungarian nobles and khan Mamai.

Michael Glinsky had been sent as a young man to the court of Emperor Maximilian I and served in emperor's army.

Winning distinction during Maximilian's campaigns against Friesland in 1498, Glinsky had been awarded the Order of the Golden Fleece.

In the service of Albrecht of Saxony during the Italian Wars, he had converted to Roman Catholicism.

Glinski has traveled extensively in Austria, Italy, and Spain.

He also studied medicine at the University of Bologna; this fact will be used against him in later life as such education had introduced him to poisons.

During his twelve-year tour of western courts, Glinsky can boast of personal connections and relationships with many members of the nobility, including Emperor Maximilian.

Glinsky had returned in late 1498, to Lithuania, where he quickly became a favorite and personal friend of Alexander Jagiellon, Grand Duke of Lithuania.

Almost immediately upon return, Glinsky becomes Grand Duke's vice-regent in Utena.

Appointed Court Marshal of Lithuania, he had become a member of the Lithuanian Council of Lords in 1500.

The following year he was granted privileges to conduct lucrative trade in wax and oversee the coin mint in Vilnius.

Due to his connections with western Europe and knowledge of foreign languages, Glinsky often acts as a foreign minister.

Such a quick rise of a young man has stirred up resentment among the local nobility.

The greatest rivalry develops between Glinsky and Jan Zabrzeziński, Voivode of Trakai.

In 1504, Grand Duke Alexander, urged by Glinsky, had confiscated land possessions of Zabrzeziński's son-in-law.

The following year, Zabrzeziński is fined, stripped of his titles, and banished from the Council of Lords along with his supporters.

However, Zabrzeziński soon reconciles with Alexander and is reinstated as the Grand Marshal of Lithuania.