On a hot day in September 1806, with flags flying, Lieutenant Facundo Melgares led some 300 Spanish army troopers and New Mexico militiamen into a large Pawnee camp on the Platte River in what is now Nebraska. Melgares, whose force had set out three months before from the provincial capital, Santa Fe, had orders to intercept and arrest certain Americans known to be traveling unlawfully in Spanish territory and said by an American informer to be descending the Missouri River. The American trespassers’ names were William Clark and Meriwether Lewis.
Melgares had departed Santa Fe on June 15 with 105 Spanish regulars, 400 New Mexican militiamen, and 100 American Indians. At the Arkansas River near present-day Larned, Kansas, Melgares left 240 men with instructions to build a fort; he led the rest of his contingent north on the king’s business. He had to tread lightly. His orders were to keep the peace with the Pawnee at all costs.
Unbeknownst to Melgares, at that moment Lewis and Clark were 140 miles east, sailing down the Missouri River toward the frontier town of St. Louis. At his village, Pawnee Chief White Wolf refused to let the Spanish continue, seemingly ready, Melgares thought, to fight if pressed. Melgares could only persuade the Pawnee to fly Spain’s flag exclusively and keep Americans off their lands. He arrested two French trappers found in the village for trespassing. Around September 11, captives in tow, he made for Santa Fe. Unaware they were targets, Lewis and Clark proceeded to St. Louis, there ending a 29-month round-trip odyssey to the Pacific.
Melgares and his men made up the last of four Spanish forces sent to arrest Lewis and Clark. Each contingent just missed its assigned troop of Americans, whether it was traveling up the Missouri or bound back to St. Louis. The Spanish considered these ventures evidence of espionage and meant to stop all four.
The American troops were following President Thomas Jefferson’s orders to map the acreage acquired when the United States bought the Louisiana Territory in 1803 from France. Spain, however, viewed that deal as illegal because in 1863, at the end of the Seven Year’s War between France and Britain, France had signed the land over to the Spanish
