Sgt. Carson A. Holmquist grew up in Grantsburg, Wis., a hamlet of about 1,400, best known for its proximity to a wildlife reserve. Grantsburg was so small that when Holmquist attended the local high school, the entire student body numbered only around 300.

But Holmquist’s decision to join the Marine Corps in 2009, a year after he graduated from Grantsburg High School, took him out of a tightknit rural town and exposed him to the world, eventually placing him on the battlefield, as far away as Afghanistan and, this week, as close as Tennessee.

On Thursday, Holmquist, 25, was killed in a shooting at a military facility in Chattanooga, Tenn., one of four Marines slain by 24-year-old Mohammad Youssef Abdul­azeez.

Josh Watt, the principal of Grantsburg High, said Holmquist was a hard-working, sociable teen, involved in school life. He played defensive back on the football team, which Watt helped coach.

“In a small community, you get to know everyone,” Watt said. “There are lots of hurting people today.”

As a youth, Holmquist was also an avid outdoorsman and spent time hunting and fishing in the woods and lakes around Grantsburg, nestled in northwest Wisconsin near the Minnesota border.

In the winter, Carson, his brother and their friends rode snowmobiles; in the summer, dirt bikes.

Taffy Pisman, who knew Carson Holmquist through his older brother, Chris, said Carson was “always smiley and funny,” she said.

Watt described Grantsburg as a “patriotic” town and said he wasn’t surprised that Holmquist had decided to join the Marines. Other friends said it seemed like a natural decision.

Watt said that Holmquist returned to Grantsburg after he completed basic training, paying a visit to his alma mater, where he met with teachers and students while wearing his dress blues.

“He looked so sharp,” Wall said. “You could tell he was very proud.”

Holmquist eventually married another small-town Wisconsin native, another friend said.

He and his wife, Jasmine, a native of St. Croix Falls, about 30 miles from Grantsburg, had one young son, Wyatt, and Jasmine is expecting a second child, another friend said, speaking on the condition of anonymity to discuss Holmquist’s personal life.

Holmquist’s parents, who are divorced, still live in the Grantsville area, friends said. None of Holmquist’s family members could be reached for comment.

According to the Marine Corps, Holmquist, who was trained as an automotive technician, was deployed to Afghanistan from September 2013 to May 2014. It was his only overseas assignment as a Marine. Later, he was stationed in Chattanooga, where he helped train Marine reservists at the facility that Abdulazeez targeted this week.

Grantsburg High School was expected to hold a candlelight vigil Friday, friends of the Holmquist family said, while there were plans to observe a moment of silence at Grantsburg’s annual snowmobile watercross championship, a major annual event for the tiny town.

Julie Tate contributed to this report.