Hidekaz Himaruya, also romanized as Hidekazu Himaruya, is a Japanese manga artist born on May 8, 1985, in Kōriyama, Fukushima Prefecture, Japan. He is best known as the original creator of the multimedia franchise Hetalia: Axis Powers. Himaruya emigrated to the United States to study at the Parsons School of Design in New York City but ultimately dropped out. He lived in New York from late 2006 until early 2009, when he returned to Japan following the release of the anime adaptation of his work and his contractual obligations with a publishing company. He is reported to hold dual nationality in Japan and the United States.

Himaruya began his career by publishing original webcomics on his personal website, including works such as Barjona Bombers and Susume Kitakou Hosobu. The most significant of these webcomics was Axis Powers Hetalia, which he started while attending school in New York. The series was subsequently picked up for professional publication as a manga by the publisher Gentosha, serialized in the magazine Comic Birz from 2006 to 2013. The title Hetalia is a portmanteau of the Japanese word hetare, meaning useless or pathetic, and Italia. The manga was later re-launched under the title Hetalia: World Stars, which began serialization in Shueisha's Shonen Jump+ magazine in September 2014 and is ongoing.

The Hetalia franchise has seen extensive adaptation into other media, most notably anime. The first anime adaptation, Hetalia: Axis Powers, was produced by Studio Deen and directed by Bob Shirohata, premiering as an original net animation (ONA) in January 2009. This was followed by a second season, Hetalia: World Series, which ran from 2010 to 2011. A theatrical anime film, Hetalia: Axis Powers - Paint it, White!, was released in June 2010, with Himaruya credited for the original story. Subsequent anime seasons include Hetalia: The Beautiful World (2013), directed by Hiroshi Watanabe, and Hetalia: The World Twinkle (2015). The most recent anime season, Hetalia: World Stars, aired in April 2021, continuing the series' adaptation of Himaruya's ongoing manga. In addition to the anime, the franchise has spawned drama CDs and a video game titled Gakuen Hetalia Portable for the PlayStation Portable.

Beyond his signature series, Himaruya has created several other manga works. He wrote and illustrated Chibisan Date, a serialized comic that ran in Comic Birz before moving to Comic Spica, which was collected into four volumes. He also created the series Taisho Roman Oni-san Yameteee!!, published in Shueisha's Jump Square magazine and collected into two volumes. In 2020, he launched a new manga titled Sori Club, which focused on personifications of Japanese prime ministers; this series concluded in October 2023.

Himaruya's artistic identity is defined by his use of comedic allegory and satire to reinterpret world history and international relations. His characters are personifications of nations, regions, and micronations, with their personalities being built from a mix of positive and negative national stereotypes. While the series initially focused on the events of World War II, particularly the Axis and Allied powers, it has since broadened to cover a wider range of historical events, cultural comparisons, and modern holidays. The core premise is that historical and political interactions between countries are represented as social interactions and misunderstandings between the humanized characters.

The creator is noted for his involvement with his fan community, sometimes affectionately referred to by fans as Papa Hima. He maintains a personal blog where he posts about his daily life and shares character sketches. Himaruya has stated that he allows the use of images from his site for non-profit fan activities such as creating original characters, fan videos, and cosplay, though he discourages the unauthorized copying of CDs. His known hobbies include photography, architecture, and collecting postcards. The commercial success of Hetalia has been significant, with multiple volumes of the English-translated manga appearing on The New York Times manga bestseller list. The series has developed a large international cult following and has been noted for its influence in popularizing the genre of national personification in anime and manga.