Silas Gaskill was born in New York in 1829 and headed to California in a wagon train at age 21, as part of the 1850 Gold Rush. His younger brother Luman, born in Steuben County, Indiana in 1843, followed seven years later with their parents, arriving by sail to San Francisco. Like many forty-niners, the family found gold elusive and tried different work — they labored at the Buffalo Gold and Silver Mining Company in Petaluma before Silas and Luman took up bear hunting.

In 1868, they left the gold country and settled in the Milquatay Valley, just a mile north of the Mexican border. The stone store they built was not just a retail enterprise — they also opened a blacksmith shop and a gristmill, ran a bee farm and a small cattle ranch. Luman, being a practical man in a place that needed practical men, also served as the town dentist, doctor, and Justice of the Peace. In 1868, he married Eliza J. Benson; they had seven children.

On the afternoon of December 4, 1875, Cruz Lopez and a group of border bandits arrived at the store. They had already killed the former Governor of Baja California, Antonio Sosa, in a robbery before reaching Campo. What followed at the Gaskill Brothers' Stone Store was a gunfight that left eight dead and two wounded.

Luman was shot in the lung. Silas took a wound to the shoulder. Both survived. The incident sent the Army east from San Diego: Company G of the 1st Cavalry Regiment was dispatched under Major General John Schofield's orders, marking the first regular military presence in what would eventually become Camp Lockett. A frontier outpost became a military necessity, traced directly to the violence at this stone building.

The store itself kept operating. The Gaskill brothers rebuilt and continued. Their tenure at the store lasted until 1901, when they sold all their properties and retired to San Diego. Luman died in Whittier, California on May 3, 1914.

After the Gaskills sold, the property changed hands in a pattern common to frontier commercial buildings: bought, resold, operated under different names, and eventually allowed to fall into disrepair. E. T. Aiken bought it first, then Klauber Wangenheim purchased it from Aiken around 1898, and Henry Marcus Johnson operated it as the Mountain Commercial Company until 1925. By the late 1930s it had deteriorated enough that E. M. Statler purchased it, gave it to San Diego County, and a restoration project ran from 1943 to 1948.

The store was recognized as California Historical Landmark No. 411 on November 15, 1948. In 1986, California State Parks, the Department of Parks and Recreation, and the Squibob Chapter of E Clampus Vitus — a historical drinking society with a sideline in historical preservation — placed a marker at the site. Today the Gaskill Brothers' Stone Store Museum is run by the Mountain Empire Historical Society.

All goods in the original store were stocked in bulk and sold by weight — flour, grain, dried beans, everything measured out as customers wanted it. The exception was prepackaged Arbuckle Coffee and Lion Coffee, which arrived in sealed form and was sold as received.

Stone construction was unusual in the California backcountry of 1868 — most builders used wood, which was faster and cheaper but vulnerable to fire. The Gaskills built in stone, which is why their store stands while the bear hunting and gold mining and blacksmithing and dentistry have faded into historical footnote.

The building at the corner of the Milquatay Valley road has outlasted the bandits, the cavalry, the various owners, and even the Army camp that the bandit raid helped create. It is the kind of structure that makes the case for permanence — stubborn, unglamorous, and still there.