One of the reasons why he was selected for Zogushi could be that there were expectations for cooperation with the Hata clan, Tanetsugu's mother's family home, located in Kadono County, the Province of Yamashiro which was close to Nagaoka, the place where the capital was transferred to.
遷都先である長岡が母の実家秦氏の根拠地山背国葛野郡に近いことから、造宮使に抜擢された理由の一つには秦氏の協力を得たいという思惑があった事も考えられる。