The first half of 1863 saw campaigning in the Mississippi Valley that was seriously to affect the future of Texas. United States forces sought to wrest control of the great river from the Southerners. As Grant maneuvered to take Vicksburg, northern Confederate stronghold on the great river, Banks moved through Louisiana in preparation for an onslaught against Port Hudson, lowest Mississippi River point still held by the South. To scatter and confuse enemy defenders, Banks advanced on Port Hudson in such a way as to endanger key points in Louisiana.[80] These disruptive thrusts caused many Louisiana planters to bring their slaves into Texas to escape possible capture.[81] Also, Banks’ probes caused many Texas regiments to be shifted to Louisiana, where they were to assist in blocking Banks’ column. Pyron’s Regiment was one such Texas force. As it hurried from Galveston towards Niblett’s Bluff, on the Sabine River enroute to Louisiana, a distinguished British military observer reported on the unit’s appearance as it paraded by: First came eight or ten instruments braying discordantly, then an enormous Confederate flag, followed by about four hundred men moving by fours—dressed in every variety of costume, and armed with every variety of weapon; about sixty had Enfield rifles; the remainder carried shot-guns (fowling pieces), carbines or long rifles of a peculiar and antiquated manufacture. None had swords or bayonets—all had six-shooters and bowie knives.[82] Finally, when Banks withdrew to the east of the Mississippi River and proceeded to concentrate against Port Hudson, most Texas commands in the area were shifted to the Red River Valley of northern Louisiana.[83] That summer the Union forces captured Vicksburg and Port Hudson, thus gaining full control of the Mississippi River. By instituting a very tight gunboat patrol system, the Union was able to transform this river into a formidable barrier that cut the Southwest away from other states of the Confederacy.[84] To size up the new situation Lieutenant General Edmund Kirby Smith, commander of the Confederate Department of the Trans-Mississippi West, called for a conference with the governors of Texas, Louisiana, Arkansas, and Missouri. The meeting was held at Marshall in mid-August of 1863. The key question to be discussed was that of Kirby Smith’s powers. While the governors showed a reluctance to admit it, the General would obviously have to become virtual dictator of the isolated trans-Mississippi region. Only in that way could the states involved gain the vital strength in leadership that would allow them to remain undefeated. Tacit recognition of Kirby Smith’s need for extensive control was indicated by the governors’ agreement that he should supervise all defenses and oversee all future cotton transactions with Mexico.[85]