It is generally thought that this sword, forged by the sword smith “Yoshiyuki,” was the one that Sakamoto Ryoma had with him when he was assassinated in Kyoto on the evening of his thirty-third birthday. Even so, it has long been a point of controversy whether or not this was actually the same sword. It is housed at the Kyoto National Museum. When I first visited the museum years ago, while researching my novel Ryoma Life of a Renaissance Samurai, I was allowed to take it in my hands. At any rate, I was thrilled!
According to a May 10, 2016 article from NHK News, the Museum more or less confirms that this was indeed Ryoma’s sword.