The man in this picture is Frederico Borrell Garcia.

Death of a Loyalist Soldier captures that heart stopping moment of death, in that instant before the soldier’s body slackens and falls to the ground. His body is suspended in mid air, and his arms are outstretched towards the sky in surrender. In its time this photograph was unprecedented in its ability to produce an emotive quality about photography thought only possible by painting. The composition is effect and the silhouette of his body against the horizon is reminiscent of realist painter Millet.

There has been some controversy surrounding this image, namely because people have accused it of being staged. The first accusation was made by a British journalist by the name of Phillip Knightley who had reportedly shared a hotel room with Capa while they were both stationed in Spain during the Spanish Civil War. On the web there is a well written article about how the photograph is indeed authentic, and it can be found here