and Burlington Route Historical Society . But I ignored Wikipedia's dates because they did not seem to be correct.
While studying rail access to an ethanol plant in Shenandoah, IA, I came across the name Burlington and Missouri River Railroad because the town was platted by that railroad. The B&MR was incorporated in Burlington, IA, in 1852. With a branch founded in 1869 in Nebraska, it built toward Lincoln, which was recently designated the state capital. It entered Nebraska via Plattsmouth in 1870 and reached the capital that summer and reached the Union Pacific Railroad at Kearney on Sept. 3, 1872. 1872 is also when it was acquired by the Chicago, Burlington, and Quincy, which had completed a bridge over the Mississippi in 1868 to connect to it. A branch north to Council Bluffs was the third railroad to reach this railroad hub. The Chicago & Northwestern and the Chicago, Rock Island & Pacific were the first and second railroads to Council Bluffs. By 1882, the B&MR had completed a bridge over the Missouri River at Plattsmouth and built an extension to Denver, CO because Jay Gould bought the UP and some other railroads around it. The extension to Denver, CO, avoided being "boxed in" by Jay Gould's empire. The CB&Q had the first direct connection between Chicago and Denver and that extension gave it access to the Denver & Rio Grande and Western Pacific as a competitive route to the UP and SP. By 1882 the locomotives had switched from burning wood to coal and had become much larger. They could pull larger, more plush coaches and diner cars had been added to the consist.
The Shenandoah web page indicates that Burlington Northern Railroad operates the line and plans to have the line improved to Hazardous Material standards for 2006. This was probably so that it can ship ethanol from a local plant. Note that this web pages is obsolete because BN was merged into BNSF in 1992. But even though the branch is run like a shortline because tank cars are parked on the "mainline," a BNSF map does show it still owns the track through Essex and Shenandoah to Farragut.
Update: Later, CB&Q built a more direct route from Kansas City to Brookfield, KS and then abandoned most of the route west of Brookfield to St. Joseph.