Henry Armstrong Miller (born July 16, 1969) is a former sumo wrestler, raised in St. Louis, Missouri, who competed under the shikona Sentoryū Henri (戦闘竜 扁利). The first wrestler from the US mainland to reach the top makuuchi division, he made his professional debut in 1988 and reached a highest rank of maegashira 12 before retiring in 2003. He last competed in MMA as recently as 2013, losing to Kazuhiro Nakamura.
He was born in Tachikawa, Tokyo, Japan, the son of a Japanese mother and African-American father. He was born on the same day that the Apollo 11 lunar mission left Earth and his middle name was given to him by his father in honor of Neil Armstrong. He lived on Yokota Air Base until the age of six, when he moved with his family to St Louis, Missouri. He grew up in Ferguson. His dream of becoming a professional football player was ended by a knee injury in his senior year of high school, but he had also been wrestling since elementary school and he had qualified for the state championships. After graduating in 1987 he returned to Japan to try professional sumo.