When in the late summer of 1864 a force of some twelve thousand soldiers under the command of Confederate major general Sterling Price were sent to capture the state of Missouri for the Confederacy, it represented a real threat to the Union.
The Reconquista, or Christian reconquest of Iberia, took nearly 800 years. The fighting did not come without great attempts by Muslim powers across the strait trying to reestablish their presence in mainland Europe. The last gasp of that effort came in the 1330s, when the powerful Marinid sultanate of what is modern Morocco invaded in an attempt to reverse Christian gains and secure the perilous position of the Sultanate of Granada.