In 1216, he became a Mandokoro betto (Secretary of government office) in the Kamakura bakufu due to the lack of talented staff (At that time, number of post of Mandokoro betto was two and Nakaakira worked with OE no Hiromoto).
それでも、鎌倉幕府初期の人材不足のためか、建保4年（1216年）には政所別当に任じられた（当時は2人制で大江広元とともに職務を担当した）。