Denrai: chicken or the egg?

Denrai are heirloom items that belonged to well known clans from the feudal era of Japan.

Some of these were very powerful regional clans and have famous warlords in their lineages, and many of them played significant roles in the history of Japan. These are clans like the Uesugi, Shimazu, Mori, and so forth. 

There are also minor clans without significant power bases. On top of this all we add the Tokugawa Shogun and the Mito, Kishu and Owari branches of the Tokugawa family who stand apart from the other daimyo. 

There are some reasons why denrai status is important, outside of the historical interest and coolness factor to have a sword that belonged to one of the major clans.

When we look at the NBTHK Juyo zufu there are about 453 out of almost 12,000 swords that went Juyo and higher that have preserved information about what clan handed them down. This is a surprisingly small number of only 3 percent and points out that it is quite rare to have one of these blades.

Chicken or the egg?

When we look at Tokuju swords the presence of these heirlooms is much more significant statistically: 320 out of 1052 have preserved history. This is about 30 percent and is very different from what we see at Juyo.

It clearly illustrates a correspondence to an established history for a sword and whether or not it has topmost ranking. 

Before getting more into it, I will say that some of the Juyo items simply have lost their history though they did belong to great collections.

Collectors are often careless, dealers don’t care at all, or in some cases daimyo deliberate destroyed evidence of their connection to a sword when it is sold. All of this disconnects the sword from its past. In Japan as well some collectors actively erase sayagaki in some mistaken belief that this is more respectul for the sword to be in unadorned shirasaya. But what they do erases important history and on these shirasaya we have lost connections. 

We know that they did this because the Juyo zufu often preserves sayagaki information and when the sword returns to the market 30 years later that sayagaki is gone. Or, some dealer took photos of the sayagaki and those photos are the only record left… thankfully I’ve seen some of these online for swords that my clients have owned and it’s allowed us to piece together some of the history of the blade.

Sometimes at Tokuju history is reconnected or reconstructed through clan documents, or it may have been recorded with the sword and just not mentioned at the Juyo level. That accounts for some but it does not account for a 10x difference. 

The initial gut reaction is that being owned by a major warlord is a bonus item on the list of features that makes a blade pass Tokubetsu Juyo. And surely it does not hurt. 

But it is very important to reverse the thinking and to realize that the best blades got sucked up by the daimyo when they encountered them. The main explanation is just that swords with known daimyo connections tend to be better swords than those without.

The more powerful you were the greater your ability to absorb the best blades by way of gifts to you, and to resist giving up those blades due to financial necessity or to please someone more powerful than yourself. 

If you are higher up the food chain, you will probably be in a better position for predation of the best swords. 

So it is really both factors at play and the chicken and the egg both have a role in this item going on to Tokubetsu Juyo when it has a connected history.

Having that preserved history is beneficial and important, but also that great sword did not end up with a powerful family by accident. The fact that it was a great sword guided it into that collection and a lesser sword would not have been pursued, accumulated and maintained over centuries.

Stealth mode

Some swords stayed in stealth mode for this the basic reason of them being great swords.

What nobody knows about doesn’t have to end up going somewhere as a gift to someone more powerful than yourself. Giving up a “newly discovered” (i.e. freshly made fake) Masamune may be more in your interests than having the great one your family has been keeping in the cache known about and subject to envy.

Sometimes these blades were bought out by more powerful people and in some of these cases the payment can probably be seen as compensation. In this the new owner has just absorbed the sword and paid for the damages to the previous owner, if the power gradient is very high. 

In essence, if you kept a sword hidden then it doesn’t have to go anywhere unless you want it to. That explains some of the best blades that have unavailable or obscured history. Even today some collectors are very quiet about what they own, where it came from and where it may go. You may talk to someone with a major treasure every day and do not know.

Standout collections

Some of the daimyo had standout collections, in some cases extending well past their economic power base.

The Uesugi clan is the best example. They were powerful but their sword collection was truly magnificent. Outside of the Tokugawa they seem to have had the best swords.

Yamanaka wrote that they had a particularly good holding of ubu swords and that they refrained from the habit of shortening these for wear. Some examples of this are a Kanemitsu known as the Mikazuki that was found in the USA and has a nagasa of just over 80 cm and a Fukuoka Ichimonji Norikane that is unaltered with a nagasa of 76 cm. Another is the Kara-kashiwa Kuninobu on the Kyoho meibutsucho which is 79.4cm.

These were not so long that they were completely unweildy, like some of the Nanbokucho period blades preserved in shrines (some of these have nagasa of 120-150 cm), but they also could have been practically trimmed and some of the signature preserved. That happened a lot of the time, but the Uesugi didn’t seem to want to do that. Instead they preserved their old blades if given the chocie.

Oda Nobunaga had a great collection and he had a reputation for doing the opposite. His favorite sword is said to be the Heshikiri Hasebe which is now Kokuho and which he shortened to 65 cm. The Yoshimoto Samonji was taken as an ubu signed tachi when the owner was killed, and Nobunaga went right about shortening it and adding kinzogan that it was Samonji, and taken as a prize. It is now 67 cm.

The Meibutsu Fudo Rai Kuniyuki was also one of his blades but since it was a kodachi of 58 cm there was no need to cut that blade down. 

Hideyoshi’s collection was magnificent and stored at the Osaka castle for the most part. He had the Kokuho Mikazuki Munechika, the Kokuho Atsushi Toshiro, the Kokuho Uraku Rai Kunimitsu, the Juyo Bunkazai Murakumo Go Yoshihiro, the Juyo Bunkazai Futsasujibi Sadamune, and a Kokuho Samonji tanto among others.

When the Tokugawa forces defeated the Toyotomi and Osaka castle burned, many of his swords burned with it. One of these was the Yoshimoto Samonji, another was the Ichigo-Hitofuri Toshiro (which is the only katana length Yoshimitsu work to have survived) and the Honebami Toshiro (a naginata naoshi attributed to Yoshimitsu with a long history and the name means Bonecutter so watch out). 

A lot of those blades ended up with the Tokugawa after Hideyoshi and Echizen Yasutsugu retempered many of the burned ones. He also made copies before or while he was doing the work. In some cases now the original is lost and all we have is Yasutsugu’s copy.

As well there is a story that on the way home from Osaka, Tokugawa Ieyasu was given a prophecy that whenever the swords from Hideyoshi reached Edo, the Tokugawa would fall from power. 

As a result these blades got shunted to the Kishu Tokugawa branch in Kii province and never made it to Edo. 10 Juyo, 21 Tokubetsu Juyo, 9 Juyo Bijutsuhin, and 6 Kokuho come from the Kishu Tokugawa collection. There are others which did not get any papers as they were not submitted for anything. 

In general the top collections by count that passed through high level papers are: 

  1. Tokugawa (Shogunate)
  2. Tokgawa (Kishu)
  3. Uesugi
  4. Hosokawa
  5. Maeda
  6. Shimazu
  7. Tokugawa (Owari)
  8. Date
  9. Kuroda
  10. Mori
  11. Ikeda
  12. Satake
  13. Matsudaira
  14. Mitsui
  15. Sakai

There may be a bit of movement up and down the list by a place or two as I need to distill this information a bit, but I think that represents a good first shot at ranking the collections by currently published items.


Having preserved family ownership is still quite rare and nice to have for a collector. Just having family mon on a koshirae is not usually enough to exactly determine who had something. Generally the power of the clan went parallel to the collection, but it is clear that some clans put more emphasis on their sword collecting than what power they maintained through the Edo period. The Tokugawa undermined many of the clans that supported Hideyoshi after they defeated the Toyotomi, and these clans fell in economic power. With that so went their swords in many cases.

Since there are only 453 with history that passed through the Juyo level, and 320 of those went on to Tokubetsu Juyo, we can see there is a strong relationship between the best swords and ownership by one of the clans. Out of 12,000 that achieved Juyo at minimum, only 453 with recorded information about the family ownership means that it should be regarded as pretty exclusive outside of recognizing the high percentages at Tokubetsu Juyo.

I will note again that sometimes in the Juyo the information was simply not recorded though that information is accessible in other ways. I have encountered this myself, for example on a Go Yoshihiro owned by the Nabeshima or on a Niji Kunitoshi owned by the Ueda. In some of these cases the family ownership has been underscored when the blade passed through Tokubetsu Juyo though it was ignored at Juyo, and I carried it back into the Juyo counts when missing and I know it exists. 

The statistics are very significant and blades owned by the Shogunate, Uesugi and others, is a significant merit badge that helps to assess the importance of the blade. The key takeaway is that it is is not just a modern viewpoint that the blade is something significant. It is a sword that has been important in the past, is import now, and will always be in the future.

Whenever we are handed down something through the past and told by those those who came before us, and were in positions to know and to fight over these things, that the item was to be treasured… that is key information for us in how to understand this kind of artifact in the present day.

Sometimes it can be a head scratching experience if there are deficiencies in the item, and in those cases it is sometimes just a case of condition not standing up through the centuries. We need to understand that when our predecessors had the blade in hand, it was a younger, and more vigorous blade than sometimes we are left with today.