Swallow, 24, replaces Brent Harvey, 33, North's captain for the past three seasons, while Jack Ziebell, 21 later this month, was announced as a vice-captain alongside Drew Petrie.
Swallow was told of his appointment by coach Brad Scott in front of the North playing group and most of the club's staff on North's Aegis Park training ground.
Shortly afterwards, Swallow said he had been working on his leadership skills in recent seasons but was still a work in progress.
"I've had a few opportunities in my junior career but I think as I go along (my leadership) will evolve," he said.
"I'm probably not someone who will be in people's faces and yelling and screaming. I like to lead by the way I play, similar to the way that 'Boomer' (Harvey) prepares and the way he goes about his footy.
"(I'll also be) just getting alongside the guys and getting to know them really well and making sure that they're travelling well."
North coach Brad Scott said Swallow's on-field status and character had earned him the captaincy.
"Andrew has got the score on the board on-field - he has really elevated himself to the upper echelon of midfielders in the AFL now," Scott said.
"And he really just reflects the type of person we want here at North Melbourne."
Scott also paid tribute to Harvey's "exceptional" reign as captain but said it was the perfect time for a leadership transition.
"Given that there are a number of players that are indeed capable and worthy of leading our club, we have decided that the opportunity to appoint a new captain while Drew and Boomer are still playing was too good to pass up," Scott said.
Harvey was "very excited" by the prospect of mentoring Swallow and Ziebell, saying he'd always wanted to play at least one more season without the captaincy before he retired.
Harvey will remain in the leadership group with Daniel Wells.
Swallow has been the Kangaroos' most consistent player over the past three years, respectively finishing first, third (one vote behind joint winners Harvey and Brady Rawlings) and first (jointly with Wells) in the best and fairest award, the Syd Barker Medal.
But Swallow's journey to North's captaincy has not always been smooth. After representing Western Australia at the 2004 NAB AFL Championships, he was overlooked in that year's drafts.
Picked up by North with pick No. 43 in the 2005 NAB AFL Draft, Swallow made an impressive start to his AFL career, playing 12 games and winning a NAB AFL Rising Star nomination in his debut season, and every match when North reached a preliminary final in 2007.
However, poor form and injury limited Swallow to just North's opening three games in 2008.
Fortunately, his luck changed on the eve of the 2009 season. Left out of North's team for its round one clash with Melbourne, Liam Anthony's late withdrawal with injury opened the door for him.
Swallow did not let his opportunity slip, racking up 21 possessions to be of the Kangaroos' best against the Demons. He has not looked back since.
Similarly, Ziebell's path to the vice-captaincy has had its share of potholes.
After being drafted by the Kangaroos with pick No. 9 in the 2008 NAB AFL Draft, Ziebell made a promising start to his AFL career in 2009, slotting straight into North's senior team and winning a NAB AFL Rising Star nomination.
However, he broke his leg in round 12 that season and another in 2010. These injuries limited him to 24 games in his first two seasons and, just as significantly, hampered his efforts to improve his endurance running.
After North's round five loss to Richmond last season, Ziebell and fellow midfielder Ben Cunnington were labelled "unfit for AFL level" by Sydney Swans premiership coach Paul Roos.
In his commentary role with Fox Sports, Roos said: "They've been next to useless today … maybe they should be playing in the (VFL) to get their fitness up."
Ziebell responded in the best possible fashion, undertaking extra aerobic sessions throughout the year and hitting a rich vein of form in the second half of 2011. From round 11, he had six games of 25 possessions or more, the highlight his 41-possession best-on-ground performance against the Western Bulldogs in round 17.
Ziebell's outstanding form reversal was recognised with a career-best finish of sixth in North Melbourne's best and fairest count.
A big-bodied 188cm midfielder, Ziebell is a natural ball-winner at stoppages and a key member of North's emerging on-ball division.
