Cumro, named by William Edmunds for his home town in Wales, was a thriving frontier settlement located between Georgetown post office, four miles to the west, and Eudell post office, three miles to the east. It boasted a school, blacksmith shop, physician, and store, with a church and cemetery to the north. Cumro post office was established in 1885 with Morgan W. Jones as postmaster and discontinued in April 1943.
In the summer of 1877, the Kearney and Blackhills Stage Line followed the South Loup River valley with stops south of Eudell and at Georgetown. A Union Pacific line planned for the valley was surveyed through Cumro in the 1880s, but the line was never built because the railroad experienced financial difficulties.
Cattlemen began bringing cattle into the valley in 1869, and conflicts erupted when homesteaders challenged the cattlemen's claim to the land. Fierce blizzards of 1880-1881 decimated the herds, hastening the end of the open range. Among descendants of the cattlemen and homesteaders who settled the area can be found such names as George, Morgan, Trew, Wood, and many others.