A Union force was raised in California to march into Confederate held Arizona at the start of the Civil War. As these men moved 900 miles to the east, the column constructed camps and forts leaving men behind to garrison them. One of these posts was Camp Mimbres, and it was raided on March 15th 1864 by a small band of Apaches. Union Captain James H Whitlock put together an expedition of 46 men in the 5th California and 10 in the 1st California Cavalry to retrieve the cows and horse which were taken. They moved towards the Sierra Bonita Mountains, when the trail turned west it led to the base of Mount Gray near present day Hidalgo County, New Mexico.
At about 4am on April 7th 1864 Whitlock spotted campfires and advanced his men on the Apache camp. He found about 250 Apaches and a herd of livestock. Whitlock had his men surround the camp and attack at the first light of day. The Chiricahua Apache fought in defense of their camp for over an hour, before retreating up into the mountains.
Whitlock had his men set fire to the camp, and destroy all the Apache’s food. There were 21 Chiricahua killed and left on the field. The Californians didn't suffer any casualties. They also took a herd of 45 horses and mules.