As a boy he worked the cotton fields of south Texas with his migrant laborer parents, but today Patricio Fernandez Flores became the preeminent Mexican-American in the nation's Roman Catholic Church.

His installation as archbishop here makes the social activist cleric the spiritual leader of 650,000 Catholics in south Texas, most of them Hispanic. s

Today's event, as much an ethnic celebration as a Catholic ceremony, called attention to the nation's growing and growingly assertive Mexican-American community as it seeks a greater share of power in the church. Though the history of Hispanics and Catholicism here is centuries-long, Flores is the city's first Mexican-American archbishop.

Flores became the first Mexican-American bishop in 1970, and his accession here makes him only the second Mexican-American archbishop in U.S. history. The first, Robert Sanchez, was named in 1973 to lead the much smaller and less visible Santa Fe archdiocese. He sat just a few feet from Flores today beside an open-air alter set up in front of San Fernando Catherdral.

Today's installation, and Flores' return to San Antonio Friday after 18 months as bishop of El Paso, produced an outpouring of affection for a man who for eight years was a guiding force for social and political change in this city.

His motorcade Friday to the cathedral was cheered by those whose causes he has championed. Along the way from the airport, Texas Farm Union banners and placards calling for support for undocumented workers were promised. The platform at a civic ceremony in the afternoon was shared by Mexican-American county judge, and Mexican-American state representatives.

Flores, a member of the board of Saul Alinsky's Industrial Areas Foundation and chairman of the Texas Advisory Committee to the U.S. Civil Rights Commission, promised today that he would not allow his new duties to turn him from his advocacy for the poor.

"We can multiply fish and bread in a different way," he told reporters between a predawn mariachi serenade for him and a midmorning mass he celebrated. "We can do it by knocking on the doors of politicians or knocking on the door of the federal government for programs."

His travels among U.S. Latinos, and his embrace of the causes of farm workers, textile mill hands and illegal aliens have given him special standing with Hispanics nationwide.

Flores' rise in the church, while naturally applauded by Mexican-American, reminded many of the extent to which they have been closed out of the church hierarchy. While almost 30 percent of the nation's 49 million Catholics are Hispanic, only 10 to 340 bishops are.

Only last year, Mexican-Americans in California fought unsuccessfully for the appointment of a Mexican-American bishop for the new diocese of San Bernardino.When Archbishop Francis Furey, 74, died here in April, an almost unheard-of lobbying effort was launched for the return and elevation of Flores, 50, who was named by Pope John Paul II to succeed Furey on Aug. 28.

Brother Trino Sanchez, a Jesuit who is executive director, of Padres, a church organization seeking more political power for Mexican-Americans in San Antinio, said that there is "elation" in "Pueblo Mexicano" over Flores' triumphant return.

But, he said, "we're still waiting to see" whether the church responds to Hispanic claims for power. Several bishops' chairs are vacant in areas with large Mexican-American populations, including Amarillo, and the one vacated by Flores in El Paso.

Reflecting San Antonio's ties with its Mexican past, the principal language here today is Spanish, and the mass that followed Flores' installation was scored with mariachi music.

Flore's flock gathered by the hundreds on Main Plaza in front of 240 year-old San Fernando Cathedral, as blue-and-white helium-front of 240 year-old San Fernando Cathedral, as blue-and-white helium-filled balloons rose toward a leaden sky while Apostolic Delegate Jean Jadot led Flores to his episcopal chair and presented him his staff. An overwhelmingly Hispanic crowd interrupted the new archbishop's homily with cries of "viva Flores!" when he promised "to show kindness and compassion for the poor at to all who are in need."

"He's just like a leader," said Luis Garza, a truck driver.

"People just love him," added Garza's wife, Erlina. "In places where he's needed the most, that's where he is. Especially with poor people.