So this is actually, disappointingly, a short answer: Spain sent zero athletes to compete in Berlin.

What a shame, right? It seems like I’ve written a lot below this disappointing answer, though, so I wonder what that’s all about?

Well, dear reader, what I’ve just told you is that Spain sent zero athletes to Berlin. However, Spain did send athletes to the Olympics.

You see, as the 1936 Olympic Games were nearing, it became seriously debated in many countries whether or not to participate in what would essentially become a parade for fascism. Notably, Spain’s newly-elected Popular Front government (a moderate coalition of center-left and leftist forces), decided to boycott the Berlin games and instead rapidly organized events to be held in Barcelona (Barcelona would later become an extremely radically leftist city during the war). These events are known in English as “The People’s Olympiad,” and were largely attended by leftists from across Europe. The games were intended to be commenced on July 19.

That last detail is incredibly important for our purposes. Coincidentally, military leaders within Spain had been in talks for some time about a military uprising against the Popular Front government. The leaders of this revolt had different intentions, like reestablishing the monarchy, or establishing a fascist state, or perhaps engaging in a “second reconquista” against “the reds.” Regardless, they intended for this uprising to begin on July 17 (!), just two days before the People’s Olympiad was set to commence (!!). On top of all of their other crimes, the fascists paid no mind to well-planned sporting events.

As the opening moves of the war swept across the country, Barcelona braced for impact. Anarchist groups demanded (and occasionally received, or stole) arms from the local government. Local police and paramilitary groups had unclear loyalties, and seemed unsure of whether to join the rising or to stay loyal to the Popular Front. And our brave Olympic athletes “waited uneasily in their hotels and dormitories.” [1] Understandably, the games themselves were cancelled, what with the Civil War, and all.

When the fighting broke out, amazingly, around 200 athletes spontaneously volunteered to join the leftist militias quickly assembling. The image that we get from this early period is quite chaotic, but these foreign volunteers were some of the earliest foreign supporters of the Republican cause, forming the nucleus of the International Brigades in the “centuria Thaelman.” Later on, the International Brigade would play an important role in the Republican Army. Other foreigners were attracted to the war (but not necessarily joining the International Brigades themselves!), including for example famous writers Orwell and Hemingway, as a volunteer in a non-Brigade militia, and as a journalist, respectively.

So there you have it! The Spanish boycott of the Berlin games eventually morphed into a shockingly revolutionary symbol of international antifascism, almost completely by accident. It is a curious coincidence that the Games were intended to be convened only 2 days after the Generals had planned their rising.

Source: Antony Beevor’s The Battle for Spain