By the mid-nineteenth century, a combination of factors caused the herds to fall into decline

Cattle

In 1880, the cattle kingdom fell. The good profitability of cattle led ranchers to increase the size of their cattle. This move led to overgrazing which depleted the plains where cattle can graze. There was also over production of cattle that led to oversupply in the market. The surplus of cattle in the market led to decline in prices. Changes in the weather conditions such as the extended summer dryness greatly reduced the cattle population. These conditions led to the fall of the cattle kingdom.

d. promised it other land