Arima Naozumi

Infobox_Officeholder | name= Arima Naozumi
nationality=Japanese
order=Arima family head
term_start= 1612
term_end= 1641
predecessor= Arima Harunobu
successor= Arima Yasuzumi
order2=Lord of Shimabara
term_start2= 1612
term_end2= 1641
predecessor2= Arima Harunobu
successor2= Arima Yasuzumi
birth_date=1586
birth_place=Japan
death_date=June 3, 1641
death_place=
spouse=

nihongo|Arima Naozumi|有馬直純 was the first son of the Christian daimyo Arima Harunobu. He was baptized as a child with the name Miguel (ミゲル). He was born in Hinoe Castle in Shimabara but was sent by his father to work beside Tokugawa Ieyasu at the age of 15. He married Konishi Yukinaga's niece Marta (マルタ); however, in order to curry favor with Ieyasu, he divorced his Christian wife and married Ieyasu's adopted daughter Kuni-hime in 1610. In 1612, he inherited his father's land valued at 40,000 "koku" in Shimabara when his father was executed for his role in the Okamoto Daihachi Incident. Tokugawa Ieyasu ordered a general persecution of all Christians in Japan, and Naozumi immediately gave up his Christian belief, exiled his former wife and secretly killed his two half brothers– 8-year old Francisco (フランシスコ) and 6-year old Mathias (マティアス).

However, he was dissatisfied with the constant revolts and chaos as a result of the Christian persecution and asked the Shogunate to transfer him to Nobeoka in Hyuga Province. When Shimabara Rebellion broke out in his old fief in 1637, he answered the call of the Shogunate and led a 4000 detachment to suppress the rebellion. He died in 1641, during his "sankin kotai" in Osaka.