Hat happened to grazing land when Fort Defiance located near Canyon de Chelly?

When the Fort Defiance was stablished in 1851 near Canyon de Chelly, a Navajo territory, the indians were prohibited to use the valuable grazing land available. Therefore, the Fort Defiance was always figthing with the Navajo people, and two great attacks were held in 1856 and 1860 against the fort. With the Civil war oncomming, the fort was abandoned. But the Navajo raids continued, so the fort was reestablished as Fort Canby in 1863. General Carlenton used it as a base operation against the indians and, when they were deported to New Mexico in the known "Long Walk", much of their livestock was destroyed. The Fort was abandoned again years later, and the remaining Navajo people burnt it.

Fort Defiance was established in 1851 by Col. Edwin V. Sumner to set military presence. The Federal Government banned the Navajos to use or access this area. Consequently, they begun fighting, ending in two attacks: 1856 and 1860. In 1861, the army left Fort Defiance, but Brigadier General James H. Carleton continued fighting the Navajos.