This is probably related to the account of Samuel de Champlain, a French explorer who, while traveling in North America, sent the first samples of the plant to France, noting that it tasted similar to the artichoke.
The name Jerusalem artichoke is believed to have originated in 1615 when a member of the Brazilian Topinamba tribe visited the Vatican at the same time that plants brought from Canada were on display there, used as a critical food source to help French settlers in Canada survive the winter.
The name has caught on and is now used in French, German, Italian, Polish, Romanian, Russian and Spanish.
