Mr. J.R. Poinsett was a US minister to Mexico in 1823. Not only was he a diplomat, but also an amateur Botanist. He sent plants home. In Mexico, this was called the Christmas Eve plant (Flor de Nochebuena).
By 1836, the plant We know as the Poinsettia was popularized in the United States.
The plants are attractive, but Rhinos don’t eat them. It’s not a problem most of the time; they don’t grow where We live.