In his words, the late professor was "an exceptional Historian and Teacher who promoted through his posture and word a critical way of thinking about the past and the present, and also to have an open outlook to the world and pursue new goals".

Gudavicius researched the history of the Grand Duchy of Lithuania and was one of the creators of Lithuania's modern historiography.

The professor identified the likely date of the coronation of King Mindaugas on July 6, 1253, and the date was later declared a public holiday.

Gudavicus was awarded a Lithuanian National Art Prize for Culture and Arts in 1998.