In the 18th and 19th centuries, the metaphor of a "crucible" or "smelting pot" was used to describe the fusion of different nationalities, ethnicities and cultures. It was used together with concepts of the United States as an ideal republic and a "city upon a hill" or new promised land. It was a metaphor for the idealized process of immigration and colonization by which different nationalities, cultures and "races" (a term that could encompass nationality, ethnicity and racist views of humanity) were to blend into a new, virtuous community, and it was connected to utopian visions of the emergence of an American "new man". While "melting" was in common use the exact term "melting pot" came into general usage in 1908, after the premiere of the play "The Melting Pot" by Israel Zangwill.