WASHINGTON — An 18th-century missionary who brought Catholicism to the American West Coast was elevated to sainthood Wednesday by Pope Francis in the first canonization on U.S. soil.

Francis canonized Junipero Serra during a Mass outside the Basilica of the National Shrine of the Immaculate Conception, the largest Catholic church in North America.

Serra was a Franciscan friar who marched north from Baja California with conquistadors from his native Spain, establishing nine of the 21 missions in what is now California. The pope announced in January that Serra would be canonized.

The decision was polarizing. Serra is revered by Catholics for his missionary work, but many Native Americans in California say he enslaved converts and contributed to the spread of disease that wiped out indigenous populations.

In his homily, Francis defended Serra, characterizing him as a kind and open-hearted man who protected Native Americans from colonizers.

“He was excited about blazing trails, going forth to meet many people, learning and valuing their particular customs and ways of life,” Francis said. “Junipero sought to defend the dignity of the native community, to protect it from those who had mistreated and abused it.”

Many Latinos in the U.S. view the canonization of a Spanish-speaking missionary as a badly needed acknowledgment of the Hispanic history of the American church. Latinos make up about 38 percent of U.S. Catholics, but are well above the majority in several dioceses.