Sigismund's son Sigismund II Augustus was crowned Grand Duke of Lithuania in the palace. Sigismund II carried on with the development work and lived there with his first wife Elisabeth of Austria, daughter of Ferdinand I, Holy Roman Emperor. She was laid to rest in Vilnius Cathedral. Sigismund II's second wife, Barbara Radziwiłł, also lived in the palace. According to contemporary accounts of the Holy See's emissary, the palace at that time contained more treasures than the Vatican. Sigismund II also assembled one of the largest collection of books and tapestries in Europe.