The Kumeyaay nation had thrived for about ten thousand years in and about the area we now call Southern San Diego County and northern Baja California. But, on the other side of the world, the King of Spain in 1765 decreed to establish colonial possession of Alta California (north of Baja California).
A four part expedition was planned by Visitor General Galvez. Portola was in charge of the military quarter of the expedition. Fr. Serra came with him and they traveled from New Spain (Mexico) by land. Three ships were also supplied and sailed from New Spain for San Diego Bay. One of the ships was never heard from again. The two remaining ships after being lost finally anchored in San Diego Bay.
The crews of these two ships, San Carlos and San Antonio, were incapacitated and dying of scurvy and thirst. Every day, two or three died. The crews and officers, which had been composed of about sixty men per ship, had been reduced to only eight soldiers and as many sailors who were able to work.
The ships had no fresh water. Finding fresh food and water was an emergency if the crew, dying of scurvy, was to survive and recover. For this purpose, the officers of the San Carlos landed on the 1st of May, with 25 of the soldiers and seamen who were best able to hike.
This party skirted the western shore of the bay (along the bay side of what is now called Point Loma) and observed at a short distance a band of Kumeyaay armed with bows and arrows. The party tried to communicate with the Kumeyaay but the band would not let themselves be overtaken.
When asked by signs where the watering-place was, the Kumeyaay pointed to a grove of trees which could be seen at a considerable distance to the northeast, giving to understand that a river or creek flowed through it, and that they would lead the men to it if they would follow. They walked for (as they described ) about three leagues till they came to the banks of a river with fresh water (San Diego River). It was lined on both sides with a heavy canopy of over spreading cottonwoods and sycamore .
The Spanish journals of the contact describe that within a musket-shot (military description) from the river (300'), outside the trees, they discovered a hamlet composed of from thirty to forty families of the same Kumeyaay who were guiding the watering party.
This was the area called Kosa'aay (which means drying out place). The village was composed of shelters made of branches, and huts, pyramidal in shape, covered with earth. As soon as they saw their companions bringing the sailors into Kosa'aay, all the inhabitants came out to receive them, and in goodwill invited the strangers into their homes
By barter fresh water and food was obtained from the Kumeyaay. The villagers wanted cloth; and it was for something of this sort would they exchange their fish or whatever else they had. And so the peaceful behavior of the Kumeyaay sustained the lives of the ships remaining personnel. The Kumeyaay reported an auspicious eclipse of the sun and earthquake when the ships had entered San Diego Bay.
On the 14th of May Captain Rivera arrived with the first land party. The land expeditions arrived in better shape although many Christian neophytes (Indian converts from Mexico) had died and the rest of the party were on half rations. They also were supplied by the people of Kosa'aay with water and food to recover their strength.
On May 15th Captain Rivera ordered the expedition's hospital camp and temporary garrison moved to their only source of food and water, the village of Kosa'aay (Cosoy). Rivera felt militarily safe doing this with the greater firepower of the land expedition's additional soldiers. The new hospital camp was sited one league farther north on the right bank of the river upon a low hill (Presidio Hill) and was "less than a musket shot" (military description) from the village. The garrison at the village site was permanent (the founding of San Diego). The crucial condition of the Expedition was demonstrate by the fact that Royal Spanish Officers along with common soldiers and sailors all labored to move the equipment and supplies of the hospital camp.
July 16th, 1769 was the date of dedication of the first mission and the first Mass on the soil of California. This was at Kosa'aay, (Cosoy) just below the hospital camp. The hospital camp on the hill gradually was fortified and became the San Diego Presidio and the first San Diego Mission. It was from this base at Kosa'aay that Spain's colonization of California and the California Mission Chain were launched.
Thus the location of Kosa'aay (Cosoy) became for the Pacific Coast of the United States what Roanoke Colony, Jamestown, and Plymouth were for the Atlantic Coast; and, from that site grew the colony that is now California. Also, on August 15th, 1769 Kosa'aay was the location of the Kumey'aay nation's first organized resistance to the cultural tyrany of the conquistadors. For these reasons Kosa'aay is of incalculable historic value to San Diego, California, and the United States of America including the Kumey'aay nation.