Nobuyuki Sanada was head of Numata Castle in Kozuke Province (Gumma Prefecture). Much trusted by Ieyasu Tokugawa, he was given the title of Governor of Izu (1593).
In the Sekigahara Battle (1600), he was the only Sanada who fought on the side of the Tokugawas. After the battle, he prevailed upon Ieyasu to save the life of his father, who had fought for the Toyotomis. Ieyasu gave Masayuki's Ueda Castle, Shinano Province (Nagano Prefecture), with a fief of 115000 koku, to Nobuyuki. He was also given Matsushiro Castle, with 130,000 koku, also in Shinano, in 1622 as reward for the part he took in Ieyasu's campaign against the Toyotomis in Osaka. He was then given the Court rank of lord chamberlain.
After retiring (1656), he became a Buddhist priest and took the name of Ittosai.
He was married to Komatsuhime (Inahime), Honda Tadakatsu's daughter and adopted daughter of Tokugawa Ieyasu.