The Kujo line of sekkan (regent and senior regent) houses, the House of Fujiwara North of the Fujiwara clan, was a kugyo (court noble) during the Kamakura period; the original forefather was Sanetsune ICHIJO, the third son of Michiie KUJO; the name of the house was due to the fact that Sanetsune had inherited Ichijo Hall, which had been built by Michiie as a residence.
藤原氏藤原北家摂関家九条流で、鎌倉時代の公卿である、九条道家三男一条実経を祖とし、道家が創建した一条殿を実経が受け継いで住んだ事が家名の由来。