Even more impressive than her age is the fact that Ardern unexpectedly found herself Labour leader six weeks ago when their previous leader, Andrew Little, unexpectedly quit.
Straight away she was catapulted into the middle of an election - one her party was losing.
You might remember Ardern's first 24 hours, as in that time she expertly shut down sexist men who asked her about plans to start a family, probing to prove her inability for the role.
Before she'd even set up her new desk, Ardern was making headlines worldwide for her no bullshit answer - "That is unacceptable in 2017."
The election was tight and resulted in no single-party majority. Both Ardern and National leader Bill English required the support of New Zealand First leader Winston Peters to form government.
Tonight, Peters announced his decision to back Labour.
Ardern learnt of her success the same time as other Kiwis - as the long-awaited announcement was made on live television.
The new Prime Minister told media she was “honoured, privileged and humbled” by the results.
“The negotiations have been courteous, constructive and robust. Throughout, we have focused on our shared values and the policies that can take New Zealand forward,” she said.
The news comes after a confronting week for women, and frankly, we couldn't be more pleased with the result.
This article originally appeared on Marie Claire.