[1] While serving as a captain in the Spanish army in 1782, José Antonio Roméu led a retaliatory action after the Quechan Yuma Massacre of 1781.

The Spanish were unable to defeat the Yuma, and the tribe remained in control of the land for the following seventy years.

The event closed the Anza Trail, crippling the overland population growth of the Yum colony.

Roméu, his wife Doña Josefa, and daughter first travelled to Loreto, Baja California Sur arriving on March 17, 1791.

He led in a time of peace and worked well with the Spanish missions in California and Franciscan padres.