After the Koan War in 1281, he ceded his position of Akitajo no suke to his heir Munekage ADACHI at the age of 52, and was instead appointed as Mutsu no kami (Governor of Mutsu) in 1282.
弘安4年（1281年）の弘安の役後、弘安5年（1282年）、52歳の泰盛は秋田城介を嫡子安達宗景に譲り、代わって陸奥守に任じられる。