The 20-year-old, selected by the Rangers with the No. 28 pick of the 2018 NHL Draft, won the Salming Trophy this season, awarded annually to the best Sweden-born defenseman in the Swedish Hockey League as selected by Hockey Hall of Famer Borje Salming.
Lundkvist scored 32 points (14 goals, 18 assists) in 52 games for Lulea of the SHL this season, leading defensemen in goals and power-play goals (eight). He scored the most goals by a defenseman in one season among players 21 years old or younger in SHL history.
"Despite his young years, Nils is already a complete player, but who will get even better," Salming told the Lulea website. "He moves the puck quickly, has a toxic shot [on the] power play. Is effective in [his] own zone. It's so easy for Nils, he plays ice hockey."
He has scored 78 points (30 goals, 48 points) in 166 games in four SHL seasons. Over the past two seasons, he led SHL defensemen with 25 goals and was second in points (63).
Lundkvist had five assists in three games at the 2021 IIHF World Championship and helped Sweden to third place in the 2018 and 2020 IIHF World Junior Championships.
He is the third player selected by New York in the first round of the 2018 draft to be under contract with the Rangers; forward Vitali Kravtsov (No. 9) scored four points (two goals, two assists) in 20 games with New York this season, and defenseman K'Andre Miller (No. 22) scored 12 points (five goals, seven assists) in 53 games with the Rangers.