Greta Thunberg is Time magazine's Person of the Year.

The 16-year-old climate change activist has become the face of a movement, according to Time's editor in chief, Edward Felsenthal who wrote, "Over the course of little more than a year, a 16-year-old from Stockholm went from a solitary protest on the cobblestones outside her country's Parliament to leading a worldwide youth movement."

Thunberg is a polarizing force. Her supporters defend her and rally behind her cause while critics have attacked everything from her looks to the way she speaks and above all, her beliefs. She has been blamed for young people hating cars and was even called a "brat" by Brazilian President Jair Bolsonaro after she condemned violence against indigenous people in the Amazon.

However controversial Thunberg's selection by Time magazine, there have been other contentious choices in the past. Adolph Hitler, Joseph Stalin, and Richard Nixon were all chosen as Time Person of the Year in the past. The magazine notes its choices reflect the person or thing that had the "greatest impact on the news, for good or ill."

Her rise from unknown activist to Time Person of Year

Here is a timeline of Thunberg's rise from an unknown, solo campaigner to the leader of a global movement:

August 20, 2018: Swedish student Thunberg, then aged 15, skips school to protest outside parliament for more action against climate change.

September 2018: Thunberg begins a regular "strike" from classes every Friday to protest climate issues. She invites other students to join her weekly "Fridays for Future" campaign by staging walkouts at their own schools.

March 2019: Thunberg is nominated for a Nobel Peace Prize. The number of students taking part in school strikes hits more than two million people across 135 countries.

May 2019: Thunberg is named one of the world's most influential people by Time magazine, appearing on its cover. "Now I am speaking to the whole world," she wrote on Twitter.

September 23, 2019: Thunberg delivers a blistering speech to leaders at the UN summit, accusing them of having "stolen my dreams and my childhood with your empty words."

September 25, 2019: Thunberg is named as one of four winners of the 2019 Right Livelihood Award, known as Sweden's alternative Nobel Prize.

(With input from Reuters)