An ancient symbol on a Norwegian Olympic team’s sweaters is stirring controversy because the Nazis appropriated the symbol during their murderous campaign to create a master race.

Going back centuries, the rune symbol has been associated with Norse mythology’s Tyr, a god of war with one hand who was linked to heroism. It had no connection to racism, as the Anti-Defamation League points out, but Nazi Germany used the symbol on some uniforms and institutions and neo-Nazis have since picked up the rune as a symbol in their white supremacist movement.

“The Tyr rune is one of many ancient European symbols appropriated by the Nazis in their attempts to create an idealized ‘Aryan/Norse’ heritage,” according to the ADL. “This gave symbols such as the Tyr rune a new, racist significance that they did not originally have.”

Sweaters that Norway’s alpine skiing team was supposed to wear at the 2018 Winter Olympics in South Korea, designed by Dale of Norway, carry the rune. The sweaters were designed with “Viking inspiration,” according to the clothing manufacturer, and the team is referred to as the “Attacking Vikings.”

“Neo-Nazis have marched with Norwegian flags,” Dale of Norway CEO Hilde Midthjell told the New York Times. “That does not mean we stop using that, does it?”

In this case, the neo-Nazis are taking a symbol that has long been associated with strength and glory in Norse mythology.

The ADL suggests taking the rune’s use on a case-by-case basis: “One should not assume that use of the symbol is racist but instead should judge the symbol carefully in its specific context.”

The Norwegian Ski Federation was reportedly giving the athletes a choice of whether they wanted to wear the controversial sweater and a couple of Norway’s Olympians told the New York Times that they were hesitant to put it on.