The rise of Labour leader and now Prime Minister-elect Jacinda Ardern has been made even more remarkable, given her age of just 37.
However, she isn't the youngest leader to take control of a country.
Here is a list of the nine youngest current leaders from around the world.
Austria: Sebastian Kurz - 31 years old
Sebastian Kurz has only recently been newly elected as the Chancellor of Austria.
San Marino: Enrico Carattoni - 32 years old
Enrico Carattoni is one of San Marino's two heads of state, known as a Captain Regent.
North Korea: Kim Jong-un - 34 years old
Kim Jong-un currently holds power in the rogue nation of North Korea.
Qatar: Emir Sheikh Tamim bin Hamad Al Thani - 37 years old
Emir Sheikh Tamim bin Hamad Al Thani took power of Qatar in 2003, after his father stepped down.
New Zealand: Jacinda Ardern - 37 years old
After Thursday night's announcement, she became New Zealand's youngest female Prime Minister.
Bhutan: Jigme Khesar Namgyel Wangchuck - 37 years old
Jigme Khesar Namgyel Wangchuck is currently King of Bhutan and took power at the age of 26.
Ireland: Leo Varadkar - 38 years old
Leo Varadkar is the current head of state in Ireland, known at the Taoiseach.
Estonia: Juri Ratas - 39 years old
Juri Ratas is the current Prime Minister of Estonia and was elected in November 2016.
France: Emmanuel Macron - 39 years old
French President Emmanuel Macron took over as leader of France from Francois Hollande in May 2017.