Abraham Lincoln's vision of a slavery-free United States was one that was supported by leaders and prominent citizens in countries around the world. One of these important figures included Giuseppe Garibaldi, a revolutionary who fought for the unification of Italy. In this, Garibaldi was very similar to Lincoln in that both men desired the unification of their countries under a single government.

In 2015, a letter matching one sent in 1865 was sent from Florence, Italy, to the United States, signalling a renewed desire to highlight the work that Lincoln did to "protect the humanity of all within its border" and the continuation of that work into the modern day.