Did a Future President Swear an Oath of Allegiance to Spain?

A young Andrew Jackson may be one of the most unlikely figures ever to swear loyalty to the King of Spain—yet in 1789, that is exactly what happened.

Born in the Waxhaw region on the border of North and South Carolina, Jackson headed west in October 1788 at age twenty-one, eager to make his way in the world. When he arrived in Nashville (then still part of North Carolina), he quickly established a law practice to support himself on the edge of the American frontier.

But Jackson rarely relied on one profession alone. To supplement his legal income, he launched a trading business not far from the Cumberland River. His ventures soon drew him farther south into Spanish territory, especially the bustling town of Natchez, Mississippi.

A Surprising Requirement in the Borderlands

By 1789, Jackson was spending enough time in Natchez to become known in its growing social circles. He even considered settling permanently after purchasing property in the area.

But doing business in Spanish Mississippi came with strings attached.

Spanish law required that all men who conducted business or owned property in Natchez swear an oath of allegiance to Spain, promising to “obey with the same exactness and loyalty as the rest of the Vassals of His Catholic Majesty.”

Jackson complied.

According to historian Robert V. Remini, the oath was a practical matter rather than a political one. Jackson “took the oath without giving it a second thought, the way a great many other Americans did at the time. It probably meant nothing to him.” On a frontier shaped by multiple empires, Americans often navigated different legal systems simply to survive and prosper.

From Spanish Ally… to Spanish Adversary

Whatever temporary loyalty Jackson offered in 1789, it did not last long.

By 1818, the same man who had sworn allegiance to Spain was commanding U.S. forces against Spanish positions and their Native American allies in Florida. Jackson’s aggressive campaign made such an impact that Secretary of State John Quincy Adams secured the Adams–Onís Treaty the following year. Spain ceded all territory east of the Mississippi River and relinquished its claim to Oregon—helping transform the United States into a transcontinental nation.

The irony was unmistakable: a man who once swore fealty to the Spanish crown had helped end Spain’s last major foothold in North America.

Why It Matters

Jackson’s fleeting oath reminds us that early America was a world of shifting borders, overlapping sovereignties, and pragmatic decisions. Before the United States extended from coast to coast, frontier Americans often adapted to local laws—whether Spanish, British, or American—to build their livelihoods. Jackson’s story offers a window into that fluid world and foreshadows the complex forces that shaped the young nation.

Source

Robert V. Remini, “Andrew Jackson Takes an Oath of Allegiance to Spain,” Tennessee Historical Quarterly 54 (Spring 1995): 2–15.

Image 1 — Inauguration Scene

Allyn Cox, “First Capitol Inauguration – 1829.” Architect of the Capitol. Public Domain.

Image 2 — Spanish Allegiance Document

Spanish Oath of Allegiance document signed by Andrew Jackson, 1789. Wikimedia Commons. Public Domain.