CNN  — 

A political scandal in South Korea which sent hundreds of thousands of protesters into the streets has cost Park Geun-hye the presidency.

South Korea’s Constitutional Court on March 10 unanimously upheld a vote by lawmakers to impeach Park, removing her from office.

The drama surrounds Park’s friend and informal adviser, Choi Soon-sil, who is accused of abuse of power and attempted fraud following claims she had access to secret government documents and intervened in state affairs.

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South Korean presidential scandal 'unprecedented'
03:16 - Source: CNN

Who are the Chois?

Park’s relationship with Choi and her father Choi Tae-min has long been controversial in Korea.

The elder Choi first became close with Park following the death of her mother at the hands of a North Korean assassin in 1974, while Park’s father, dictator Park Chung-hee, was president.

According to the Korea Times, Choi founded the Eternal Life Church in the 1970s, mixing aspects Christianity, Buddhism and indigenous Korean religion Cheondism, which incorporates elements of shamanism.

Choi named himself a modern day Buddha and called for all people to strive for eternal life.

A confidential 2007 US diplomatic cable, published by Wikileaks, referenced rumors that Choi had “complete control over Park’s body and soul during her formative years and that his children accumulated enormous wealth as a result.”

After Park’s father was assassinated in 1979 by the then director of the Korean equivalent of the CIA, his killer cited Choi’s relationship with the younger Park as one of the reasons.

Even members of Park’s family expressed concern. Her younger sister Guen-ryong and brother Ji-man filed a petition in 1990 to then-President Roh Tae-woo expressing concerns that Choi was manipulating Park.

Protesters wear masks depicting Choi Soon-sil and Park Geun-hye.

What influence did Choi Soon-sil have?

After her father died in 1994 at age 82, Choi Soon-sil succeeded him as church leader and spiritual mentor to Park, as the former first daughter became a political force of her own.

“The family has had an extraordinary influence over Park Geun-hye for essentially her entire adult life,” David Kang, a Korea expert at the University of Southern California, told CNN.

“It’s much more than simply, ‘oh she knows this person,’ it’s deeply intertwined, almost like they’re Rasputin and Park Geun-hye is just a puppet.”

Though she never held an official position, recent revelations showed that Choi was given advance access to presidential speeches and other documents.

Local media and opposition parties have accused Choi of abusing her relationship with the president to force companies to donate millions of dollars to foundations she runs.

In a televised apology, Park said Choi looked at “some documents” for a certain period of time after Park took office, but didn’t specify what they were.

“I am shocked and my heart is breaking for causing public concern,” Park said.

Shamanism and cults

While much of the outrage has surrounded Choi’s alleged influence over Korean politics, the scandal has also shone a light on the prevalence of cults and alternative religious movements in the country.

Korean shamanism, or Muism, is an ethnic Korean religion with similarities to Japanese Shintoism.

According to the Korean Ministry of Culture and Tourism, Muism “focuses on solving the problems of daily life through communication between humans and the spiritual world, with shamans acting as liaisons.”

Newly-wedded brides and grooms at a Unification Church mass wedding on February 17, 2013.

The country is also home to the Unification Church, known as the “Moonies” for founder Sun Myung Moon, famous for mass weddings and allegedly forcing members to disconnect from their families.

While Christianity and Buddhism dominate Korean religious life, some churches incorporate shamanistic practices and many people consult with fortune tellers or shamans.

Choi’s movement mixed strands of all three faiths, and claimed the ability to communicate with the dead and produce objects offering magical protection, according to Korean media.

During Park’s inauguration, the President stood in front of a tree bedecked with colorful silk purses, reportedly recommended by Choi to bring prosperity and good fortune.

Thousands of South Koreans march to demand President Park Geun-hye to step down on October 29, 2016, Seoul.

Chaos in Korea

As the Choi scandal unfolded, hundreds of thousands of Koreans braved the brutally cold winter temperatures to protest on the streets of Seoul.

Though Choi was arrested, South Korean presidents are immune from prosecution for anything but insurrection or treason, and Park’s term wasn’t due to end until 2018.

Calls for her impeachment soon became deafening, and the National Assembly voted in December to strip Park of her executive powers by a vote of 234 to 56.

Four months later, the Constitutional Court upheld that vote, ending the presidency of South Korea’s first female leader, and on March 24 Park was arrested on charges relating to abuse of power, accepting bribes and leaking important information.

The country will hold a presidential election on May 9 to choose Park’s replacement.

CNN’s Euan McKirdy, Elizabeth Joseph and Yoonjung Seo contributed reporting.