It' sung in Czech, because it was common at the time. Singers were not allowed to travel in the days of early communism in Czechoslovakia. Some people emigrated, like e.g. Jarmila Novotná, but many artist's international careers were ruined by the Nazist and the subsequent Communist regimes.
Beno Blachut was arguably the best Czech tenor. This piece was recorded in 1955, when he was 42. For example, Christopher Lee once said Blachut's was one of the greatest tenor voices he had ever heard.
Watch videos with other singers performing Vesti la giubba:
Recitar! Mentre preso dal delirio, non so piů quel che dico, e quel che faccio! Eppur č d'uopo, sforzati! Bah! sei tu forse un uom? Tu se' Pagliaccio!
Vesti la giubba, e la faccia in farina. La gente paga, e rider vuole qua. E se Arlecchin t'invola Colombina, ridi, Pagliaccio, e ognun applaudirŕ ! Tramuta in lazzi lo spasmo ed il pianto;Change into laughs the spasms of pain; in una smorfia il singhiozzo il dolor, Ah! Ridi, Pagliaccio, sul tuo amore infranto! Ridi del duol, che t'avvelena il cor!
English Libretto or Translation:
To recite! While taken with delirium, I no longer know what it is that I say, or what it is that I am doing! And yet it is necessary, force yourself! Bah! Can't you be a man? You are "Pagliaccio"
Put on the costume, and the face in white powder. The people pay, and laugh when they please. and if Harlequin invites away Colombina laugh, Pagliaccio, and everyone will applaud! into a grimace the tears of pain, Ah!
Laugh, Pagliaccio, for your love is broken! Laugh of the pain, that poisons your heart!