Jaime Ramón Mercader del Río (Spanish: [raˈmom meɾkaˈðeɾ]; Catalan: Jaume Ramon Mercader del Río [rəˈmom məɾkəˈðe]; 7 February 1913 – 18 October 1978)[1] was a Spanish communist and NKVD secret agent who assassinated the revolutionary Leon Trotsky in Mexico City in August 1940.

Jaime Ramón was raised in France by his mother Caridad, who also was a communist who fought in the Spanish Civil War, and also served in the Soviet international underground.

As a secret agent of the NKVD, Mercader met with the war correspondent David Crook, an English communist and volunteer soldier for the Republican side, in the city of Albacete, Castilla–La Mancha,[4] and there taught him the Spanish language and trained him in the techniques of espionage.

In 1939, a man from the Bureau of the Fourth International communicated with Mercader;[7] and the student Ageloff had returned to Brooklyn in September 1939, where Mercader joined her under the assumed Canadian identity of Frank Jacson, facilitated by and with the passport of Tony Babich, a Canadian volunteer soldier in the Spanish Republican Army killed in battle.

Trotsky had been the subject of an armed attack against his house, mounted by allegedly Soviet-recruited locals, including the Marxist–Leninist muralist David Alfaro Siqueiros.

[10] Through his lover Sylvia Ageloff's access to the Coyoacán house, Mercader, as Jacson, began to meet with Trotsky, posing as a sympathizer to his ideas, befriending his guards, and doing small favors.

[13] Caridad and Eitingon were waiting outside the compound in separate cars to provide a getaway, but when Mercader failed to return, they left and fled the country.

Mercader stated: ... instead of finding myself face to face with a political chief who was directing the struggle for the liberation of the working class, I found myself before a man who desired nothing more than to satisfy his needs and desires of vengeance and of hate and who did not utilize the workers' struggle for anything more than a means of hiding his own paltriness and despicable calculations ...

[7]In 1943, Jacques Mornard was convicted of murder and sentenced to 20 years in prison by the Sixth Criminal Court of Mexico City.

According to Stephen Schwartz, he was initially identified as Ramón Mercader by the Catalan reporter Víctor Alba, whose finding was later confirmed by the US counterintelligence project Venona.

He claimed to be an experienced mountaineer, and bragged to police interrogators, "I had a rare ability to handle the piolet, since two blows were sufficient for me to crack through an enormous block of ice".

Trotsky's grandson, Esteban Volkov, stated that he is "unconcerned" about the fate of the alleged murder weapon and wondered "if it is the real axe."

The ice axe was bought by Keith Melton, an American collector and author of books on the history of espionage, and is now on display at the International Spy Museum, in Washington, D.C.[17][16][18] Shortly after the assassination, Joseph Stalin presented Mercader's mother Eustaquia Caridad with the Order of Lenin for her part in the operation.

However, contrary to the agreed-upon conditions, she not only led that attempt at a distance but traveled to Mexico, where she was known not only as the mother of Mercader, but also as an organizer of the assassination.

He divided his time among Czechoslovakia, from where he traveled to different countries, Cuba, where he was the advisor of the Foreign Affairs Ministry, and the Soviet Union for the rest of his life.

Cuban author Leonardo Padura Fuentes' 2009 novel El hombre que amaba a los perros ("The Man Who Loved Dogs") refers to the lives of both Trotsky and Mercader.