Complex sentence: Though Nobunaga was Nobuhide's legitimate successor, the Oda clan was divided into many factions, and the clan was technically under the control of Owari's "shugo", Shiba Yoshimune.
Split into simpler sentences: Though Nobunaga was Nobuhide's legitimate successor, the Oda clan was divided into many factions. Furthermore, the entire clan was technically under the control of Owari's "shugo", Shiba Yoshimune.