The Tumblr history blog Unhistorical has over 150,000 followers, several among them students at Homestead High School. But few know they had walked past its owner every morning inside their school hallways.

“Some people who I know followed it without knowing that it’s me,” said Kathryne Cui, owner of Unhistorical. “It’s not like a secret but it’s kind of strange with thousands of people following you.”

Cui, Homestead graduate and Johns Hopkins University sophomore, runs an “On This Day in History”-style Tumblr blog, with a following that spans across continents. Her posts have reached over 100,000 notes (“liked” or “reblogged” by other users), launching her into the spotlight on Tumblr’s official history directory. And she is rarely without her bulky, black laptop, which usually has four to six history sources and a draft of a new post open.

But three years ago, she was simply a zealous APUSH student and history trivia bowl whiz.

“I just remember being in high school and being excited writing stuff,” Cui said. “I was randomly Googling history stuff I learned in APUSH and was interested in, so I figured I might as well do something educational. So I decided I’ll just learn something new every day.”

Cui updated Unhistorical daily, with topics ranging from film history, the Civil War or late 20th century leftist protest movements. And of course, she had a special photoset dedicated to Alexander Hamilton, her “number one historical figure,” on his 255th birthday. It was dubbed “Ham-spam” in her caption.

Unhistorical’s main posts feature a photoset of an event, usually cleaned up and neatly composed on Photoshop, with a multi-paragraph description underneath. Sometimes, Cui will also share paintings and music clips from a certain culture and era.

The fateful post that ultimately launched Cui into “Tumblr-famous” status featured the 100th anniversary of the Titanic setting sail. Due to what Cui guessed were “romantic associations with the movie,” the post dispersed through the Tumblr community, and she found her blog featured in the Tumblr directory spotlight.

Writing these posts is more than a side hobby, however. History, to Cui, is important for everyone to know. With news outlets churning headlines on contentious, nuanced topics such as the Gaza-Israel conflict regularly, Cui finds history as an anchor where “the answer becomes pretty clear” regarding many current events issues. She fears being “shortsighted and sheltered.”

“History is not just cute pictures in a textbook; it’s our entire political existence,” Cui said. “You need a valid understanding of history or else you don’t know anything. It’s always relevant.”

Cui believes that as a resident of Cupertino, an upper-middle class town that’s 63 percent Asian, it was difficult at first “to get a handle on what society as a whole is like” due to its geographic isolation and unique culture. It’s a place that at times is “removed from politics.” She sees the Internet as a haven to learn as much as she can outside the Silicon Valley bubble, from sources with other backgrounds and social issues.

Unhistorical isn’t “hard-hitting analyses,” Cui said, although it does aim to “raise questions.” She doesn’t get political on her blog, but instead tries to anchor posts in concrete facts of what she wants people to take away from the event.

“I put what is vital for a clear representation of the essence of what is happening,” Cui said. “I don’t want it to be an isolated event.”

Cui is quiet in her internet fame. She still thinks of herself as a “random, young college student.” Her about page says she doesn’t “pretend to be an expert on anything ever,” and she is quick to affirm that. Nonetheless, her years as a Tumblr history personality haven’t been for naught. Her understanding of history has matured with her.

“I remember being 16 and blogging and I said a lot of stuff that in retrospect was stupid,” Cui said, amused. “It’s embarrassing to go back because some things are badly written or I have a poor handle on the subject matter. But I feel kind of nostalgic because I remember learning about some of these topics for the first time in high school.”

There’s more pressure these days. Getting a lot of hits on a post is exciting but also daunting, due to the vast audience her blog has amassed. The Tumblr social justice community, never afraid of political or historical scuffle, are always on the back of her mind. Cui sometimes feels nervous before writing — a blogger’s form of stage fright.

Cui has no definite career goals as of now, but she’s considering working in the government—anything that “works toward the general good of people in society.” This summer, she’s been working at the Freedom Archives in San Francisco, digging through audiotapes from the 60s to the 90s. The afternoons spent playing tape records in the office basement add another dimension of the past to her.

“History tells you a lot about a people,” Cui said. “What kind of art they produce and what they write about and build … their spirituality and beliefs. I realize there’s so many different cultures and that humans can produce really beautiful stuff.”

Back at her laptop, Cui lets out a breath as she tapped in her final words. Her cursor zooms around her screen until it lands on “Publish.” She has never been one to proofread.