Ontario Premier Doug Ford has responded to Donald Trump’s “Lake America” renaming order with a giant “Lake Ontario. Now and Always.” sign on the Canadian shoreline, as tensions between Canada and the U.S. continue.

Trump renames Lake Ontario to "Lake America," prompting rejection from Canada's Prime Minister amid escalating trade tensions.

Trump’s executive order may change the name in the U.S., but Canada isn’t required to follow suit. Here’s who gets to decide and where the centuries-old name came from.