World War I, also known as the Great War, was a global conflict that marked a turning point in human history. For Puerto Rico, an island in the Caribbean under U.S. rule, this conflict brought profound changes that reverberated through its political, social, and economic landscape. This article will explore the unique experience of Puerto Rico during World War I, from the Jones Act to the role of Puerto Rican soldiers and the war’s lasting impact on the island.

Puerto Rico Before World War I

In the years leading up to World War I, Puerto Rico was undergoing a process of substantial transformation. Having been ceded by Spain to the United States as a result of the Spanish-American War in 1898, the island found itself under new colonial rule. The Foraker Act of 1900 established a civil government, though with a structure that maintained strong American control. The U.S. President appointed the governor and other key officials, including the executive council that also functioned as the upper house of the legislature.

The American administration brought about significant changes in education, implementing English as the language of instruction, and reforming the agricultural economy towards a more capitalistic model. This period was also marked by fluctuations in the island’s economy, with sugar becoming a primary export crop. Still, a sense of political uncertainty prevailed as the U.S. Congress held absolute power over the island’s affairs.

One important figure during this time was Luis Muñoz Rivera, a prominent journalist, poet, and politician. He was instrumental in advocating for more self-governance for Puerto Rico and played a key role in the passage of the Jones Act, which we’ll only touch on briefly here as it will be more thoroughly discussed in a later section.

The Outbreak of World War I and the Jones Act

When the war broke out in Europe in 1914, the United States initially remained neutral. However, by 1917, events such as the sinking of the Lusitania and the Zimmerman Telegram led the U.S. to join the conflict on the side of the Allies. Coinciding with this was the passage of the Jones Act, which granted U.S. citizenship to Puerto Ricans. This allowed the U.S. to draft Puerto Ricans into military service just as the nation was entering the war.

Puerto Rican Soldiers in World War I

With the U.S.’s entry into the war in 1917, around 20,000 Puerto Rican soldiers served in various capacities. Notably, many served in segregated units due to the racial policies of the time. The most famous of these was the “Porto Rico Regiment of Infantry”, which was later renamed the “65th Infantry Regiment”. Though initially kept on the sidelines, the regiment was eventually deployed to guard the Panama Canal, one of the most strategically important locations for the Allies.

Another key figure of the time was Lieutenant Teófilo Marxuach, a member of the Porto Rico Regiment of Infantry, who is recognized as the officer who fired the first shot in World War I on behalf of the United States. This incident took place when Marxuach fired a warning shot from a cannon at a ship approaching the San Juan Bay, enforcing the neutrality of the United States, which had not yet entered the war.

The Socio-economic Impact of World War I on Puerto Rico

World War I had far-reaching socio-economic impacts on Puerto Rico. The war economy led to an increased demand for Puerto Rican goods, particularly sugar, leading to a temporary economic boom. However, the war also brought inflation and a cost of living increase. Socially, the war and the Jones Act altered Puerto Rico’s relationship with the U.S., sparking debates about identity, citizenship, and the island’s political future.

Post-War Puerto Rico

In the wake of the war, Puerto Rico grappled with the changes brought about by the conflict. While the war had brought some economic benefits, it also exacerbated the island’s economic dependence on the U.S. Additionally, the experiences of Puerto Rican soldiers and the effects of the Jones Act continued to shape Puerto Rico’s quest for political identity and autonomy.


The First World War was a turning point in the history of Puerto Rico. The participation of Puerto Rican soldiers not only added a new layer to the island’s relationship with the United States but also contributed to the evolving Puerto Rican identity. Soldiers like those in the 65th Infantry Regiment and Lieutenant Teófilo Marxuach played crucial roles, their service demonstrating both the opportunities and challenges presented by the island’s new status as a U.S. territory.

In many ways, World War I amplified Puerto Rico’s ongoing quest for self-determination. The war itself, the Jones Act, and the service of Puerto Rican soldiers all became part of a larger narrative about Puerto Rico’s place within the American sphere and the world at large. As we reflect on this critical period in Puerto Rico’s history, we can see its enduring legacy in the island’s political, cultural, and social landscapes today.