sˈɪdʒɪsmˌʌnd hɪmsˈɛlf wʌz mˈoʊɾᵻvˌeɪɾᵻd baɪ sˈʌtʃ ɐn ɐlˈaɪəns bɪkˈʌz tʃˈɑːɹlz vˈiː wʌz ɡˌɛɾɪŋ klˈoʊsɚ tə ɹˈʌʃə, ðˈʌs θɹˈɛʔn̩ɪŋ pˈoʊlənd ˌɔn tˈuː fɹˈʌnts.
Sigismund himself was motivated by such an alliance because Charles V was getting closer to Russia, thus threatening Poland on two fronts.