Oda Nobunaga, along with Toyotomi Hideyoshi and Ieyasu Tokugawa are considered the three unifiers of Japan. In 1467 to 1603 (Sengoku period) power was fragmented between more than two hundred feudal lords (Daimyos).
To describe the personality of the three unifiers, there is a very famous Japanese poem:
Where a monk asks the three leaders what each would do if a bird didn’t sing.
Oda Nobunaga replied: I will kill you if you don’t sing.
Toyotomi Hideyoshi replied: I’ll make him sing.
Ieyasu Tokugawa replied: I will wait until he sings.