His effort of protecting the castle compelled Ieyasu TOKUGAWA and others to write to Nagamori to surrender and he finally surrendered the castle to the enemy without incident, and as a result there were many offers to retain him because of his loyalty and competency however he decided to serve under Takatora TODO who was from the same village for an extraordinary pay of 20,000 koku.
徳川家康らによって、長盛に書状を書かせるまで城を守り通した後に、無事に開城もすませ、その忠義と力量に仕官の誘いが相次いだが、同郷でもあった藤堂高虎に2万石の破格の待遇で仕えることとなる。