The victory by Confederates in the Red River Campaign and its Arkansas segment, the Camden Expedition, opened a brief window of opportunity for Arkansas Confederates. Missouri General Joseph Shelby was dispatched to northeast Arkansas with his cavalry brigade and began recruiting. Throughout the summer of 1864, Confederate strength in northeast Arkansas steadily grew with many men who had either deserted from their previous commands or become separated, returning to Confederate Service. The last formation of new Confederate units occurred during this time with the formation of the 45th through the 48th Arkansas Mounted Infantry units. Several existing Arkansas units were converted to Mounted Infantry and dispatched to northeast Arkansas. Shelby was eventually able to seriously threaten vital Union lines of communication along the Arkansas River between Helena and Little Rock, and for a while it appeared that Confederates would mount a serious attempt to retake the Capitol in Little Rock. However, Confederate authorities in Richmond were pressuring General Kirby Smith to dispatch some of his infantry to reinforce Confederate armies east of the Mississippi. This caused uproar with the Arkansas Confederate infantry units and as a compromise, General Smith approved a plan by Major General Sterling Price to organize a large-scale raid into Missouri that would coincide with the November 1864 Presidential Elections. Many Arkansas troops would participate in the last Confederate offensive operation in the Trans-Mississippi Department when General Price lead a large cavalry raid into Missouri in the fall of 1864. Following Price's defeat at the Battle of Westport in on October 23, 1864, most of the Arkansas cavalry units returned to the state and were furloughed for the remainder of the war.