After having gone to school in St. Gallen, he moved to Vienna at the end of 1501, where he took up studies at faculty of arts the university, in particular under Conrad Celtis and Matthias Qualle.

A study trip through northern Italy brought him to Trent, Venice, and Padua, where he met the Irish scholar Mauritius Hibernicus.

The beginning of the Reformation in Switzerland (he was a friend of Huldrych Zwingli) made him, who had never had a theological schooling, study ecclesiastic texts.

When he was elected mayor of the city in 1526, he led the conversion of St. Gallen to Protestantism, and managed to maintain that new state even after the victory of the Catholic cantons in the Second war of Kappel.

Modern critical edition with German translation in 3 vols: Joachim Vadianus, De Poetica by Peter Schäffer (Humanistische Bibliothek, Reihe II: Texte, 21, I-III).