James, a four-time N.B.A. most valuable player, will make his regular-season debut for the Lakers on Thursday night when they visit the Portland Trail Blazers. He has been adamant that his decision to sign with the Lakers this summer was a basketball move — he wanted the challenge of resurrecting a storied franchise, friends and associates say — but there is no doubting the importance of his longtime ties to Los Angeles and his attraction to this place, a symbiotic relationship that can be traced to his teenage years.

“His home will always be Ohio,” Mark Olivier, one of his former youth coaches, said in an interview. “But this is a new stage of life for him.”

James’s first exposure to Southern California — specifically, Southern Californians — came in the eighth grade, when his summer league team, the Northeast Ohio Shooting Stars, took a 20-hour van ride to Orlando, Fla., to play in a national tournament. In the championship game, the Shooting Stars ran into a juggernaut: the Southern California All-Stars, which had several sets of flashy uniforms and the swagger to match. James, who later wrote in a memoir that he thought the California players were ridiculously arrogant, missed a 3-pointer at the buzzer, and his team lost.

The game stuck with James, who described his feelings in “LeBron’s Dream Team: How Four Friends and I Brought a Championship Home,” which he wrote with Buzz Bissinger.

“I have since been to Southern California many times,” James wrote. “It is a cool and beautiful place, filled with riches and glamour and secret places hidden in the pockets of the Hollywood Hills. But right then and there, I hated Southern California.”

A year later, James made his first trip to California, to play in a tournament in Berkeley for the Oakland Soldiers, an elite Amateur Athletic Union program. The back story of how he came to play for them is complicated — lots of stuff with James is complicated — but a friend of one of the Soldiers’ founders had seen James play in Akron.