there's a temple (Fuangong 福安宮) in Dongshi, Jiayi that worships a god called Yiaigong (義愛公).
The god is dressed in a Japanese police uniform. It's to commemorate Morikawa Seijiro 森川清治郎 who came to Taiwan in 1897.
At the time southern Taiwan was a tough place to live in. The lack of irrigation, long periods of drought and soil salinization made farming difficult. Most of the inhabitants were illiterate, and had poor hygiene. Morikawa was assigned to Dongshi, and immediately worked to improve locals' lives.
He setup a school at Fuangong, and taught the locals Japanese himself. He would award good students with paper and pen. He also worked to improve local hygienic situation by instructing villagers to dig sewage drains. He worked to improve soil salinization and offered the sick assistance.
The Japanese colonial government placed a heavy tax burden on the locals who had very little to begin with. Morikawa petitioned to reduce tax and was accused of placating to the locals. Morikawa was first punished, and then forced to collect all the backed taxed within his term.
On April 7, 1903, Morikawa went to Qingangong (慶安宮) and left a note that said "Tyranny disrupts civic life (苛政擾民)", then proceeded to commit suicide with a rifle. He was 42.
The grief stricken villagers buried Morikawa and decided to worship him at the temple where he taught the locals Japanese. He was referred to as Yiaigong (義愛公 The god of justice and civic love), but now more commonly known as Riben Wangye (日本王爺, the Japanese royal lord).