This refers to the people groups already living in Canaan. Translate this so the term "nations" is clarified as people. AT: "the people of the nations defiled themselves" (See: [[rc://en/ta/man/translate/figs-metonymy]])
Yahweh forcibly removing the people from the land is spoken of as if the land were a person who vomited the people out. AT: "I forcibly removed the people from the land, like a person vomits up food" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-personification]])