Peru declared its neutrality. August 21, 1916

Peru declared its neutrality in the Great War.  That it would need to do so shows the vast extent of the global conflict.

That there would have been any risk of Peru being drawn into the conflict was surely small, but keeping in mind that the British and Germans had clashed on the seas off of South America, and that indeed South American ports would come to see British and German warships visiting in ways that weren't always fully welcome, it makes sense.