He served as Chancellor of Lithuania between 1443 and 1458 and was a very close advisor and mentor to Casimir IV Jagiellon before he became the third Jagiellonian King of Poland.

He served as governor of Smolensk for around four years until 1440 assassination of Grand Duke Sigismund Kęstutaitis forced him to leave this position.

The news in Kingdom of Poland about proclamation of Casimir as Grand Duke was met with hostility towards Lithuania, even to the point of military threats.

He successfully initiated the expansion of the Council of Lords' powers, made structural reforms, led assault on rebelling Kiev.

However his son, Martin Goštautas was named the voivode of the newly created (upon death of prince Olelkowicz) Kiev voivodeship in 1471.