I was horrified by the portrayal of Nobunaga here, but it must be said that it had interesting bits that are worth a mention, so I decided to write about it.
Oda Nobunaga appears on the first two movies of the series, Shinobi no mono and Zoku shinobi no mono, both directed by Yamamoto Satsuo, and he's played by the unexpected Wakayama Tomisaburo.
I said "unexpected" because since his rough physique du rôle, Wakayama sure looked more fit to characters like the wandering ronin (see his work on Kozure Ookami) rather than that of the neurotic daimyo that he's playing here.
Yet, because of his bulky features, I think that he rendered quite effectively "ogre-ness" that Nobunaga's figure is supposed to suggest in these movies.
Long story short, the first three movies of the first arc of this saga are about the legendary ninja and thief Ishikawa Goemon and his vendetta against Nobunaga first and Hideyoshi later.
It started as a ninja duty, suggesting how Koga and Iga ninja joined the farmers and monks's rebellions against Nobunaga's ambition, and later developed into a private revenge when Oda armies would kill his little son out of gratuitous cruelty and when Hideyoshi's armies will attack the Saiga clan, causing the death of Goemon's wife.
Besides the obvious "vendetta story", the subplot of the movies is that ninja manipulated the history of Japan, and its more eminent figures and their fates, behind the shadows.
As the third movie is focused on Hideyoshi and his fall, the first two followed Nobunaga's ascension to power and the various attempts of Goemon to kill him.
Shinobi no mono is quite naive and superficial on the issue of Nobunaga's portrayal, and I don't hide that I found the movie quite boring in many points.
When he's not torturing ninjas or thinking of ways to torture ninjas with his batshit crazy son Nobukatsu (the subtitles call him him randomly also Nobuo or Nobumasa, but it's always the same person, just in case you wonder), Nobunaga is portrayed as a cruel, but all in all also a quite cool and diplomatic figure, that doesn't leave much an impression on the watcher.
Yet, it's interesting to follow Nobunaga's rise to power and how those events are lived by the ninja clans, that in mani parts look more worried that the population than they assume to protect.
Things will change with the second movie, Zoku Shinobi no mono, which is my favourite of the series.
Here Nobunaga is more defined as a character, and we're shown a good amount of the behavious that made him (in)famous: his bad temper, his little care for other people's feelings and the little effort to read them, but also his generosity with those faithful to him and his soft spot for a comfortable life.
This movie granted us also one of the most vivid sequences of the Honnoji accident: the tenacious fight of Nobunaga and Ranmaru shows all the will and determination behind these figures, and it's a pity that the epic image of Nobunaga's fight against the men of Akechi had to be shadowed by Goemon's ambush in the temple, where Nobunaga met quite a gory and sad end.
I'll end this post with a trivia: it looks like the Shinobi no mono series, expecially these first one, acted as a source of inspiration for Ronald Dahl, who was in charge for the screenplay of You Only live Twice.
Not only the attempt to kill Nobunaga with poison by Goemon, but also the iconic gestus of Blofeld to pet cats is a thing that Nobunaga is shown doing various times in the movies.