Cattle had been herded through Missouri in the decade before the Civil War, so it was natural that the practice would continue once that unpleasantness had ended. But there were hard feelings in Missouri beyond those left unresolved by the end of the war.

Cattle from Texas tended to carry ticks with them; these ticks carried so-called Texas Fever or Spanish Fever. It didn't harm the hardy longhorns, but it was deadly to the weaker breeds of cattle in Missouri. Everywhere the Texas cattle passed, or lingered for the night, became deadly to the domestic cattle of Missouri -- and the Missourians didn't know that the tick was the cause, for a long time. The Missouri livestock died by the thousands, particularly during the late summer of 1855, and again in 1858.

The Missouri Legislature passed a law forbidding movement of any kind within the state of any livestock known to be carrying Texas or Spanish Fever. Vigilance committees were formed by Missouri farmers to turn back the herds at various county boundaries.

Cattlemen began to take their herds up along the Kansas-Missouri border to St. Joseph or to Kansas City -- until Texas Fever began to break out along the new routes. Kansas passed a law similar to that of Missouri, but the Civil War delayed tests of the Kansas law.

Cattle drives began again in 1866 after the end of the war, but the problem with Texas Fever hadn't gone away. Nor had the laws banning passage of Texas cattle.