Editing Lewis and Clark Expedition (section)

=== Spanish interference ===
In March 1804, before the expedition began in May, the Spanish in [[Santa Fe de Nuevo México|New Mexico]] learned from General [[James Wilkinson]]{{#tag:ref|After Wilkinson died in 1825, it was discovered that he was a spy for the Spanish crown.|group="note"}} that the Americans were encroaching on territory claimed by Spain. After the Lewis and Clark expedition set off in May, the Spanish sent four armed expeditions of 52 soldiers, mercenaries {{explain|date=May 2021}}, and Native Americans on August 1, 1804, from [[Santa Fe, New Mexico|Santa Fe]], New Mexico northward under [[Pedro Vial]] and José Jarvet to intercept Lewis and Clark and imprison the entire expedition. They reached the Pawnee settlement on the [[Platte River]] in central Nebraska and learned that the expedition had been there many days before. Vial's attempt to intercept them was unsuccessful.<ref>[[#Uldrich|Uldrich, 2004]] p. 82</ref><ref>[[#Ambrose|Ambrose, 1996]] p. 402</ref>