‘Age of Samurai: Battle for Japan’ Full Review (Pt. 1)

Age of Samurai: Battle for Japan Logo for Netflix

It has been almost a year since the docuseries Age of Samurai: Battle for Japan has been released on Netflix. Considering how much time has passed, I was not going to bother with an episode-by-episode review of this show. I have since found out that this docuseries has been nominated for a Realscreen Award in 2022 for Best Non-Fiction—History and Biography Program.(1) Since it has been nominated for an award, now seemed to be the perfect time to go back and revisit this horrendous documentary.

A couple of things I would like to address before we begin. First and foremost, I did not want to hate Age of Samurai. This was a golden opportunity to create a fantastic documentary on one of the least talked about eras in Japanese history and it fell flat of many viewers expectations. They also managed to get a lot of people who are respected in their field, however, because they had so many, it was hard to keep track of who was saying what, and sometimes they either said things that were completely wrong, or they contradicted one another. The biggest issue with Age of Samurai was that it became more about style than substance. It was trying to appeal to fans of Game of Thrones, and while this era of Japanese history may have that vibe, it seemed that they lost sight of the fact that this was a documentary rather than a drama.(2) History seemed to fall at the wayside in Age of Samurai, making it hard to watch for people who know their Sengoku history.

Secondly, this article is not going to focus on the costumes, customs and locations. Many other content creators and historians have commented on this, and I will leave a list at the bottom of the article for people I think have done a great job talking about these things. They are more of an expert on these things than I am. This article is going to be focusing on the history that they give us in the docuseries, basically going through it like an episode of Mythbusters. Since this is going to be a long review, I will be splitting this up. For this article, part one, we will be focusing on episodes 1-3, while part two will be about episodes 4-6. This is going to be a long one, so hang on.

Episode 1: The Rise of Nobunaga

Oda Nobunaga has he appears in Age of Samurai: Battle for Japan

The first episode of Age of Samurai: Battle for Japan starts off in 1551 and ends with the Battle of Okehazama in June 1560. This is an interesting place to start, for most historians, when talking about Oda Nobunaga, usually start in one of two places: his birth in 1534 or jump to Okehazama in 1560. Instead, without giving the audience enough background to figure out how Japan got to this age of civil war, the episode starts off with the death of Oda Nobuhide. This is to help set the stage with Nobunaga, portraying him as a ruthless and ambitious man. From there, it moves on to one of the lesser-known parts of Nobunaga’s history, which was the civil war within the Oda clan and the unification of Owari. The episode ends with Okehazama with Nobunaga being thrusted into the limelight as a force to be reckoned with. So, what are the historical problems with this episode?

Hirate Masahide

I understand when it comes to documentaries that you can only have a certain amount of information, because you are not only trying to help your audience learn something new, but you also have to keep them entertained. Despite this, they really messed up when it came to Hirate Masahide’s death. For those who may not know, Hirate Masahide (1492-February 25, 1553) was a samurai who served the Oda clan and was Nobunaga’s mentor and surrogate father.(3) While it is true that Hirate Masahide committed seppuku, the reason that the docuseries gives is not entirely truthful.

To begin, Hirate’s death was not an immediate result of Nobunaga’s deplorable behavior at his father’s funeral. The docuseries paints it out to be this way, but Hirate’s death was not until 1553 and there were other possible reasons for his suicide. One of Nobunaga’s first tests as a leader took place in 1553 when one of his father’s retainers and his son left the Oda clan and joined the Imagawa. Nobunaga rose an army in retaliation, but it failed miserably. Many believe that Hirate committed seppuku because of this failure of Nobunaga’s while others believe that it was because of his son’s disobedience. The story goes that Hirate’s son, Gorozaemon, came to a field practice with a fine horse that Nobunaga liked. When Nobunaga asked Gorozaemon to give him the horse, Gorozaemon refused his lord, saying that he needed the horse to serve Nobunaga to the best of his ability.(4) Apparently, this happened around the same time as the failed battle, so either one is a possible reason for Hirate’s suicide, but either reason does not change the aftermath. Contrary to how Age of Samurai has portrayed him in the early years, before Hirate’s death, Nobunaga did not take his role as clan leader seriously. Hirate’s death caused Nobunaga to get serious about leading the clan, which lead to Nobunaga being the first in over one hundred years to get close to reunifying the war-torn country.


We have talked about Nōhime here on the website and on our YouTube channel, and unfortunately, information on her here in the West is a bit scarce. While they were right about the rumors that surrounded her, the one I could not find any claims for was the rumor that she was possibly conspiring with Oda Nobuyuki. None of the articles I have found on her mention anything about her possibly working with her brother-in-law, but they do mention that it was believed that she was sent to kill Nobunaga or sent to spy on the Oda and report back to Mino. Interestingly, we do know that she remained as Nobunaga’s wife, so it is unclear if there were any motives of possible deception. These things did happen in this era, as we will see later on, but to say if this was the case for Nōhime, we cannot be sure.(5)

Oda Nobuyuki’s Death

This is an instance of style over substance in this documentary. In this episode, it is stated that Nobunaga executed his own brother, Oda Nobuyuki, once he learned that he was planning a rebellion. While this narrative seems more appealing, it is not the truth. It is true that Nobuyuki was planning to rebel against his brother, but he was not killed by Nobunaga’s hand. He was actually killed by Kawajiri Hidetaka at Kiyosu Castle in 1558.(6)

Unification of Owari

Before the death of Nobuyuki in November 1558, Nobunaga fought against Oda Nobukata at the Battle of Ukino. It came across in the documentary that the battle was at Iwakura, but the siege actually did not take place until the following year.(7) The historians seemed to contradict one another considering that they keep referring the Battle of Ukino as Iwakura. Perhaps this was an editing flaw, but there is a difference between the two.

The Battle of Ukino is the one depicted in the episode. I have not been able to find anything about the number of guns used in this battle, which was their major talking point, but because they decided to make that their focus, they glossed over a duel that was far more epic than a prequel to Nagashino.

There was a duel fought between the famed archer Hayashi Yashichiro, who fought under Nobukata, and famous gunner Hashimoto Ippa. They exchanged blows with their respective weapons, which resulted in injuries for both men. While the duel ended in a draw, Ippa would live beyond the Battle of Ukino. The wounded Yashichiro kept fighting but was killed by Sawaki Yoshiyuki.(8) The documentary was right on one thing: there were reports of over 1,250 casualties sustained by the enemy forces.(9)

The Siege of Iwakura took place the following year and it lasted only a couple of months. Nobunaga used fire arrows, rifles and other tactics to wear down the castle’s defenders and the enemy finally gave in, surrendering the castle to Nobunaga.(10) With the fall of Iwakura Castle, Oda Nobunaga finally unified Owari Province.

Battle of Okehazama

There are a couple of things about this that I found problematic. The reenactment portrayed the battle as a night attack…just because it was surprise attack, that does not mean that it took place at night. The famous story from this battle is that a thunderstorm masked their movements, while others state it was high winds, but regardless, the battle was fought during the day.(11)

Then there is the detail that some people picked up on that made us scratch our heads. In the reenactment, the scout who notifies Nobunaga of Imagawa Yoshimoto’s movements and kills him at the battle is later revealed to be Toyotomi Hideyoshi. This is no true in the slightest. In fact, the two samurai who dealt the killing blow to Yoshimoto were Mori Shinsuke and Hattori Koheita.(12)

Episode 2: Seizing Power

Akechi Mitsuhide at Mout Hiei in Age of Samurai: Battle for Japan

The second episode skips over ten years and Nobunaga’s march on Kyōto so it can focus on the problems with the Ikkō-ikki and the Battle of Nagashino. In this episode, there was some good (not all of this was bad) and there is at least on subject that we will cover in a different article.

The Ikkō-ikki

The episode’s main focus is on the Ikkō-ikki, the Buddhist warrior monks. The documentary did a good job explaining who they were and what they stood for, especially for an episode that is an hour long. Honestly, the Ikkō-ikki need an episode all their own, but for a documentary that was trying to cover sixty-four years of history in six, hour long episodes, their explanation worked. Yet, there was some problems once they started talking about the history of the Ikkō-ikki and Nobunaga.

For starters, the year that they claim is the year for their attack on Enryaku-ji, the large monastery that sits on Mount Hiei, is wrong. They state that the attack happened in August 1570. This was actually the year and month that Nobunaga attacked another large monastery, Ishiyama Hongan-ji.(13) The massacre at Mount Hiei took place on September 30, 1571.(14) Again, I’m not sure if this was an editing mistake or if the two sieges got mixed up, but nevertheless, the information was incorrect.

There was an interesting claim made in the episode that I have not been able confirm, nor deny. The historians claimed that many of Nobunaga’s generals were appalled by the needless violence that took place there, and that this was the event that caused the relationship between Nobunaga and Akechi Mitsuhide to suffer. It is possible that Nobunaga’s generals were sickened by the massacre, but to make it the reason that would lead to Mitsuhide’s later betrayal, however, I have not been able to find anything that states that he was upset by his lord’s actions. In fact, most of them state that he was present for the massacre, while only a couple state that due to his location, he might not have participated in the actual slaughter.(15) I get that they were trying to set the stage for his betrayal later on, but there are so many reasons given for Mitsuhide’s actions at Honnō-ji that we are not sure on them to this very day.

Takeda Shingen

In order for us talk about the Battle of Nagashino, we have to talk about Takeda Shingen first. I cannot complain on how they introduced him, since in the span of this docuseries, he is only a minor player, but it the cause of death for Shingen that is tripping me up. According to the episode, they stated that the consensus is that Shingen died of liver cancer. That might be true for his rival, Uesugi Kenshin (which we have talked about before) but I cannot confirm that as the “consensus” for Shingen.(16) Shingen’s cause of death remains a mystery, yet one of the most famous causes is that he died from a gunshot wound given to him by a sniper.(17)

I would go on and talk about the events that followed, but I would like to save this discussion for the review on the 1980 Akira Kurosawa film, Kagemusha.(18)


I actually have no complaints here. They covered Nagashino extremely well and I was happy to see that they let the younger historians take over. Nathan Ledbetter, Elijah Bender and Isaac Meyer dominated the discussion on Nagashino and honestly, it was the best part of the docuseries thus far. It was clear that they knew what they were talking about, and they were more entertaining to listen to than the others that they have brought in. It was also refreshing to see that there are younger historians out there who specialize in this area. While Stephen Turnbull is main historian they go to in this docuseries (with good reason), he has been doing this since the 1970s and he will not be doing this forever. This documentary showed us who the next generation of Japanese historians in the West in a matter of a few moments.(19)


I covered this in my “brief” review when Age of Samurai first came out, but it is still one of the points that bothers me in this series.(20) While I am not in any way defending Lady Tsukiyama, some history was left out that would explain her actions. To start, a reminder on who Lady Tsukiyama was. She was Tokugawa Ieyasu’s first wife who was related to the Imagawa clan who would later be executed on suspicion of betrayal. The documentary focused on this but their reasoning for why Tsukiyama tried to betray her husband seemed, well, sexist.

According to the episode, Tsukiyama sent a letter to Takeda Katsuyori, Takeda Shingen’s son, telling him that she would betray her husband to them, but in exchange she wanted to marry a Takeda general and have them provide sanctuary for her son. The reason? She was jealous of Ieyasu’s numerous concubines. Yeah, no. It’s a lot deeper than that.

While it is possible that Tsukiyama was jealous of Ieyasu’s concubines (they said nineteen to twenty in the episode, which is excessive) this was most likely not the end all, be all reason for her wanting to betray her husband. If we do some family history, we learn that Tsukiyama is the daughter to Ii Naohira and one of Imagawa Yoshimoto’s ex-concubines.(21) Imagawa Yoshimoto was married to none other than Takeda Shingen’s own sister.(22) She most likely felt betrayed by her husband after he sided with the clan that destroyed her family, so she reached out to the only family she had left: the Takeda. The “jealous wife” reasoning seemed like a sloppy explanation for something that goes far deeper than a wife who did not like the numerous concubines in the house. Those of us in the modern world cannot really fathom the need for concubines, but they were important in those days. Concubines produced legitimate heirs and more concubines meant more children. Many women died during childbirth in those days and illnesses could kill off a bloodline, hence why multiple women and children were needed for a clan to prosper in these times. Wives usually worked with concubines, but that does not mean that there were not problems. Yet, to make this the number one reason why Tsukiyama betrayed her husband just seems more like a modern take on her situation, rather than understanding her culture and bloodline to find the true reason.

Nobunaga’s Paranoia

Towards the end of the episode, they reveal that Nobunaga was beginning to see enemies everywhere. The two things that they cite for this is the issue with Lady Tsukiyama and his survival of a recent assassination attempt, however, there are so many other things that happened in the years they skipped that would have added to it.

In this episode, they cover ten years, 1570-1580. During this time, he was betrayed by his brother-in-law, Azai Nagamasa, which resulted in Nagamasa’s death in 1573. Nagamasa’s betrayal did bother Nobunaga, but that is not the only betrayal he would suffer from. There was also Matsunaga Hisahide in 1577. This, on top of everything else, most likely increased his sense of paranoia, not just the assassination attempt and Tsukiyama’s betrayal.

One last thing, they mentioned in the episode that the ninja who tried to assassinate Nobunaga was from the Iga clan. Sugitani Zenjubo, the sniper that almost killed Nobunaga, was actually from the Kōga clan.(23) Another example of changed information to further the narrative, because they needed to find some way to bring in what they would cover in the next episode: the Tenshō-Iga War.

Episode 3: The Demon King

Oda Nobunaga at Honnō-ji in Age of Samurai: Battle for Japan

For this episode, it picks up where the last left off and began talking about the Iga and ninjas. From there, it dives into the Honnō-ji Incident, through Yamazaki and to the events leading up to the Battle of Shizugatake in 1583. Let’s dive on in.

Mochizuki Chiyome

We have talked about her on the website before, so I will not go into too much detail, but they make her out to be one of these Iga “ninjas”, the group the historians keep claiming is a thorn in Nobunaga’s side.(24) Yet, Chiyome was not from Iga, but from Kōga.(25) Even still is the fact that she actually served the Takeda clan, information that they completely disregard for the sake of moving the plot forward. Again, this is an instance where I believe that Age of Samurai should have been a drama series, for they are changing facts to fit the narrative.

The Tenshō-Iga Wars

We have talked about this briefly on the website with the article on Momochi Tanba, however, a lot was drummed up for dramatic affect. The first was the first initial attack on the Oda forces. While it is true that Oda Nobukatsu wanted to take the province to prove himself to his father, what is not true is this was a surprise attack. The Iga knew where the Oda where because they were building a castle to launch an attack from. They found out about it and attacked the Oda before the Oda could attack them. Nobukatsu wanted to invade after the loss of this castle, but his advisors told him to wait. He did, but only for a year. He launched a three-prong attack into Iga, but again, they expected the Oda and attacked. Nobukatsu was defeated and even lost a senior general. The historians claim that Nobunaga wanted to execute Nobukatsu for this blunder but all I have been able to find is that Nobunaga thought about disowning his son, not executing him.(26)

The common misconception is that Nobunaga moved to invade Iga immediately after Nobukatsu’s failure in 1579. Even the documentary makes this claim. However, the reality is that the Second Tenshō Iga War did not take place until two years later after two men from Iga came to visit Azuchi and offered to be guides for the invasion. Everything else about the second invasion seems spot on except for the end when they bring in Momochi Sandayū for a moment, just to show his execution. As we have talked about, it has not been confirmed that Momochi Tanba died after the Second Tenshō Iga War or not. Popular belief is that he did die, but others believe that he managed to escape and live another fourteen years.(27)

Akechi Mitsuhide

I realize they were trying to make him more of a sympathetic character in comparison to Nobunaga, but they get a lot wrong when talking about Akechi Mitsuhide. While it is true that he was a late comer to the Oda clan (around 1568), he was not a rōnin. In the years leading up to joining Oda Nobunaga, he served the “wandering shōgun”, Ashikaga Yoshiaki. They also claim that he had no ties to the Oda clan, which is again, untrue. It is highly possible that Akechi Mitsuhide and Nōhime, Nobunaga’s wife, were related.(28) Then there is also the claim that Mitsuhide’s mother was killed because of Oda Nobunaga. The story goes that during the invasion of Tanba Province, Mitsuhide struck a peace treaty with the Hatano clan by sending his mother as a hostage. Nobunaga instead executed Hatano Hideharu, the head of the clan, and in retaliation for the act, the retainers of the Hatano clan killed Mitsuhide’s mother. While this is one of the many things that they state were reasons for Mitsuhide’s betrayal, unfortunately, this might be Edo folklore, as this story only began circulating years after the events that led to Honnō-ji.(29)

The Honnō-ji Incident

I cannot really say anything about the events of the Honnō-ji Incident, for we do not have a clear idea of the events. There are different accounts of Nobunaga’s final moments, so it is as much of a mystery as the reasons behind it. However, there was one problem and perhaps it was because someone misspoke. They state that Oda Nobutada was at Azuchi Castle, which became Mitsuhide’s next target, but Honnō-ji was not confined to just the temple. Nobutada was actually at Nijō Castle nearby, which was attacked and Nobutada was killed there.(30) Considering that Nobunaga did have a son named Nobutaka as well, it could have been an easy mistake, but it is confusing.

Since Shizugatake is covered in episode four, we will cover the events leading up to and during the battle in part two.

Here are the links to those who get more technical about the docuseries:

The Shogunate did a video on his thoughts about the docuseries and even recommended another channel that went through episode-by-episode with a fine-tooth comb.

SengokuStudies YouTube channel did a video, mainly focusing on the trailer, but still points out the problems that can be found in the reenactments.

Sengoku Daimyo Facebook Page is another good place to go. While his podcast covers early Japanese history (for now), he covered the docuseries on his Facebook page, so some digging will have to be done.

Samurai History & Culture Japan Facebook Page is run by Chris Glenn, who recently released a book on Sekigahara, and also wrote a post about the things that bothered him about the reenactments.


  1. “Realscreen Awards 2022 nominees unveiled”, Realscreen.com. https://realscreen.com/2021/11/23/realscreen-awards-name-2022-nominees/, last visited 1/8/2022
  2. “A Samurai Version of ‘Game of Thrones’ is Coming to Netflix”, Distractify.com. https://www.distractify.com/p/netflix-samurai-game-of-thrones, last visited 1/8/2022
  3. “Hirate Masahide”, Wikipedia.com. https://en.wikipedia.org/wiki/Hirate_Masahide, last visited 1/8/2022
  4. Chaplin, Danny. Sengoku Jidai: Nobunaga, Hideyoshi, and Ieyasu: Three Unifiers of Japan (2018), pp. 58-59
  5. For the article on Nōhime, click here, and for the YouTube video on Nōhime, click here.
  6. Ōta, Gyūichi. The Chronicle of Lord Nobunaga (2011), p. 93
  7. “The Battle of Ukino, August 1558”, SamuraiWorld.com. https://samurai-world.com/the-battle-of-ukino-august-1558/, last visited 1/8/2022
  8. “Battle of Ukino”, SengokuJidai.org. https://sengokujidai.org/battles%E3%80%8C%E5%90%88%E6%88%A6%E3%80%8D/battles/battle-of-ukino%E3%80%8C%E6%B5%AE%E9%87%8E%E3%81%AE%E6%88%A6%E3%81%84%E3%80%8D/, last visited 1/8/2022
  9. “Battle of Ukino”, SengokuJidai.org. https://sengokujidai.org/battles%E3%80%8C%E5%90%88%E6%88%A6%E3%80%8D/battles/battle-of-ukino%E3%80%8C%E6%B5%AE%E9%87%8E%E3%81%AE%E6%88%A6%E3%81%84%E3%80%8D/, last visited 1/8/2022
  10. “Iwakura Castle, Aichi Prefecture”, SamuraiWorld.com. https://samurai-world.com/iwakura-castle-aichi-prefecture/, last visited 1/8/2022
  11. “The Battle of Okehazama”, SamuraiWorld.com. https://samurai-world.com/the-battle-of-okehazama-june-12-1560-oda-nobunaga-2500-vs-imagawa-yoshimoto-25000/, last visited 1/8/2022
  12. “The Battle of Okehazama”, SamuraiWorld.com. https://samurai-world.com/the-battle-of-okehazama-june-12-1560-oda-nobunaga-2500-vs-imagawa-yoshimoto-25000/, last visited 1/8/2022
  13. “Ishiyama Honganji War”, Wikipedia.com. https://en.wikipedia.org/wiki/Ishiyama_Hongan-ji_War, last visited 1/8/2022
  14. “Siege of Mount Hiei”, Wikipedia.com. https://en.wikipedia.org/wiki/Siege_of_Mount_Hiei, last visited 1/8/2022
  15. “Mitsuhide Akechi”, KoeiWiki.com. https://koei.fandom.com/wiki/Mitsuhide_Akechi, last visited 1/8/2022
  16. For our article on Uesugi Kenshin, click here, and for our YouTube video on Uesugi Kenshin, click here.
  17. “Takeda Shingen”, Wikipedia.com. https://en.wikipedia.org/wiki/Takeda_Shingen, last visited 1/8/2022
  18. Link for review will be place here once it has been published.
  19. Isaac Meyer is most famous for his “History of Japan” podcast. If you haven’t checked it out, click here for the link to his website!
  20. For the shortened version of this review, click here.
  21. “Lady Tsukiyama”, Wikipedia.com. https://en.wikipedia.org/wiki/Lady_Tsukiyama, last visited 1/8/2022
  22. “Imagawa Yoshimoto”, Wikipedia.com. https://en.wikipedia.org/wiki/Imagawa_Yoshimoto, last visited 1/8/2022
  23. Yoda, Hiroko & Matt Alt. Ninja Attack! True Tales of Assassins, Samurai, and Outlaws (2012), p. 67
  24. For the article on Mochizuki Chiyome, click here.
  25. Yoda, Hiroko & Matt Alt. Ninja Attack! True Tales of Assassins, Samurai, and Outlaws (2012), p. 59
  26. “Tenshō Iga War”, Wikipedia.com. https://en.wikipedia.org/wiki/Tensh%C5%8D_Iga_War, last visited 1/8/2022
  27.  For the article on Momochi Tanba (AKA Momochi Sandayū), click here.
  28. For the breakdown on this relationship, visit the article on Nōhime.
  29. “Honnō-ji Incident”, Wikipedia.com. https://en.wikipedia.org/wiki/Honn%C5%8D-ji_Incident, last visited 1/4/2022
  30. “Honnō-ji Incident”, Wikipedia.com. https://en.wikipedia.org/wiki/Honn%C5%8D-ji_Incident, last visited 1/4/2022