Sigismund II Augustus
On 17 May 1537 he married Barbara Radziwiłł, later the second wife of the Grand Duke of Lithuania and King of Poland Sigismund II Augustus. Goštautas died on 18 December 1542, leaving some of his family fortune to his wife, who later might have passed it on to her branch of the Radziwiłł family, while the bulk of his estates was taken by the Grand Duke of Lithuania Sigismund II Augustus, as a matter of sovereign's right.