In this essay we analyse through a historical and lexical approach an important problem of Spanish and Italian Renaissance history of poetry and language. Since the second part of the Sixteenth century, in some poetical anthologies published in Italy, together with the 'classical sonetti' and 'canzoni', we find some poems 'a la manera italiana' written in Spanish language. The authors of these lyrics are, most of all, Italian poets, who show a deep acknowledgement of Castilian language, certainly due to the daily relations that they had with Spanish literates, captains and ambassadors living in Italy because of the needs of the Imperial administration and army. These Italian poets also disguise themselves and change their names in hispanic forms, in order to look like “perfect” Spanish courtiers. These verses written in Castilian not only represent one orthodox attempt to celebrate, directly in their own language, the most important personalities of Spanish power in Italy, but also show the deep cultural, political and linguistic consciousness of Italian Renaissance poetry