A San Francisco statue that was revealed on Friday has prompted a response from Japan for its controversial nature.

But what makes it so contentious?

Located in St. Mary’s Square and created by Californian Steven Whyte, it looks simple enough: a depiction of three young girls with a grandmother figure standing nearby.

The three girls in the statue represent women from Korea, China and the Philippines, while the grandmother symbolizes the survivors still hoping for justice.

And the inscription on the statue reads: “This monument bears witness to the suffering of hundreds of thousands of women and girls euphemistically called ‘Comfort Women,’ who were sexually enslaved by the Japanese Imperial Armed Forces in thirteen Asian-Pacific countries from 1931 to 1945.”

The history of comfort women

Mainstream historians say that as many as 200,000 women and girls from occupied countries such as Korea, China and the Philippines were forced to work in brothels run by the Japanese Imperial Army. Though once rarely acknowledged, survivors of these brothels began to speak publicly about their experiences in the 1990s, and soon there were widespread demands for Japan to apologize for the wartime practice.

Comfort women statues

This would be the first “comfort women” statue in a major U.S. city.

It is part of a growing trend: Statues dedicated to Japan’s wartime sex slaves have cropped up worldwide over the past six years.

In 2011, the first statue memorializing comfort women appeared. A bronze likeness of a girl sitting by an empty chair was placed outside the Japanese Embassy in Seoul. The empty chair allowed a visitor to sit alongside the young victim. Some supporters put winter accessories on the girl, as if to protect her from the cold. The statue was installed to commemorate the 1,000th weekly demonstration outside the embassy by survivors and supporters demanding an apology from the Japanese government.

There are reported to be 40 in South Korea and 10 in the United States, including in Virginia’s Fairfax County, New Jersey and Southern California.

Japan’s response

Jun Yamada, the Japanese consul general in San Francisco, told WorldViews that the installation was “destined to be yet another addition to the existing quagmire surrounding ‘controversial statues.’”

A spokesman for Japan’s Foreign Ministry said the statue was “regrettable and incompatible with the position and efforts of the government of Japan.”

A 1993 statement by then-Chief Cabinet Secretary Yohei Kono acknowledged imperial Japan’s use of sex slaves after a government study into the issue and offered “sincere apologies and remorse” to those affected. In 2015, Japan and South Korea “finally and irreversibly” reached an agreement under which Japan pledged to contribute $8.3 million to a fund for the 46 surviving South Korean victims.

However, the agreement has been criticized by activist groups, which said they had not been consulted enough.

You won’t find these women in textbooks. But in their families, they made history.

For Women’s History Month, we wanted to document lesser-known firsts

History remembers Wolfgang Mozart. But his sister was a genius, too.

And she wasn’t the only female prodigy shut out of success

How one of the country’s leading feminist scholars would rewrite the ERA

Catharine MacKinnon argues the amendment doesn’t go far enough to enshrine all women’s rights