The river was named Río de San Francisco Xavier by the Ramon expedition in 1716 and is also recorded in the journals of the Aguayo expedition of 1721. On his map of 1828 Stephen F. Austin mistakenly labeled the river "San Javriel" — his erroneous transposition of "San Xavier." From this, the name morphed into "San Gabriel." The San Xavier missions were founded in 1745 along the river a few miles upstream from the mouth of Brushy Creek — one of the river's minor tributaries. In May, 1839 the San Gabriel was the site of the battle of the San Gabriels, one of the state's most important Indian fights. Brushy Creek was the location of the battle of Brushy Creek in February, 1839.