Did you know that, when looking at world history, only the remains of just five leaders have been preserved forever? Moreover, while some remained in a perfectly intact state for nearly 100 years, others were cremated midway. Behind this isn’t just a technological breakthrough—there are also deep marks of the choices made by the times.

It starts with Lenin. In fact, he was a pioneer of modern permanent-body preservation. When he died in 1924, he was apparently originally scheduled to be buried normally. However, there was an intense wave of public mourning, and the body began to deteriorate, so an emergency freezing procedure was carried out. This is how the history of Lenin’s cryogenic preservation began.

What’s interesting is that the first cryogenic plan was canceled after just one month. But Soviet scientists didn’t give up—they repeatedly conducted experiments and developed a special embalming solution. By replacing the body’s water content to suppress the growth of bacteria, they created an innovative technology for that era. This became the core technology that made Lenin’s cryogenic preservation possible.

Today, Lenin’s tomb is equipped with constant-temperature cooling equipment, and specialists in the laboratory constantly oversee and manage it. There is weekly restoration work, and regular comprehensive maintenance is also carried out. Sometimes even small transplant surgeries are necessary. Because of such a strict process, his body has been kept in a nearly complete state for almost 100 years.

But Stalin’s case is different. Even though he was a Soviet leader, after being buried in Lenin’s tomb in 1953, he was moved for cremation in 1961. Why? Because it went against the prevailing values of the time. In other words, the fate of body preservation is determined not only by technology, but also heavily influenced by the political judgments of that era.

Ho Chi Minh of Vietnam wanted cremation during his lifetime, but his successor decided on preservation. During the Vietnam War, his body was secretly kept in a mountain cave for 5 years, and Soviet specialists completed the embalming treatment in the underground cave while avoiding bombings. That kind of historical background is part of the story.

The preservation of the body of Nétú in Angola faced even more technical challenges. Soviet specialists specially developed pigment preservation technology for Black skin to solve the issue of pigment leakage. These days, it is said that his remains are publicly displayed only once a year, on his birthday.

Meanwhile, because Gottwald’s embalming technology was insufficient, his body decayed and was cremated in 1962. Dimitrov was preserved for more than 40 years, but along with political changes in Eastern Europe, he was cremated and buried in a public cemetery. A Mongolian leader was also embalmed and placed in a mausoleum, but in 2005, the mausoleum was destroyed, and in the end he was cremated following Buddhist rites.

So, you see: the permanent preservation of bodies is a dual product of both technology and history. It can only exist when both scientific and technological support—exemplified by Lenin’s cryogenic preservation—and the political understanding of each era are in place. The body inside the crystal coffin is not only proof of technology, but also a mirror of history.