 When many citizens of the area left after the New Madrid earthquakes of 1811–12, Walker maintained his cattle operation in the area and steadily increased his holdings.When Missouri was added to the Union, its original border proposal in 1818 was to be an extension of the 36°30' parallel north that formed the border between Kentucky and Tennessee, which would have excluded the Bootheel.However, Walker argued that the area had more in common with the Mississippi River towns of Cape Girardeau, Ste.