Walker grew up in Sydney after he and his family emigrated from the United Kingdom when he was 2. After his brother Ryan was exposed to the sport, it became clear Nathan had pro potential and he moved to the Czech Republic at age 13 to play minor and then junior hockey.
"It definitely made me a little bit more independent earlier on," Walker said. "I think it just made me mature quicker."
On the ice, Walker said practicing twice a day with HC Vitkovice's under-18 and under-20 teams helped his game mature.
"It's definitely a big jump," Walker said. "You've got a lot more time to work on your skills while you're younger."
Walker has played just seven games in the Australian Ice Hockey League back home. Internationally, he had six points in four games as Australia won the International Ice Hockey Federation World Championship Division II in 2011 and then two assists the next year in the IIHF World Championship Division I.
Walker said he hasn't thought much about being the first Australian to play in the NHL.
"At the end of the day, I'm just another guy on the team, another guy in the league, another guy playing the sport we all love," Walker said.
Walker is no stranger to NHL history. After playing for the United States Hockey League's Youngstown Phantoms and American Hockey League's Hershey Bears, Walker became the first Australian selected in the NHL draft when the Capitals took him in the third round in 2014.
Washington general manager Brian MacLellan has noticed significant strides in Walker's game since then.
"He's developed into a good penalty killer," MacLellan said. "We've always liked his speed and his compete level, those were the two things that we really liked about him. He just continues to become a better player - better positionally, he reads the game better, more intelligent on his reads - instead of being a pure energy player."
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