Vatican City — Pope Francis on Wednesday formally gave his blessing to the canonization of Junipero Serra, an 18th-century missionary credited with evangelizing California at a high price for native Americans.

The pontiff had already announced that he would be declaring the Spanish-born Serra a saint at a Mass in Washington DC during his visit to the United States in September.

Opponents of the move had unsuccessfully petitioned the Vatican in a bid to block sainthood, as they had when Serra was beatified by John-Paul II in 1988.

John-Paul subsequently made a 1992 statement in which he formally asked for the forgiveness of native Americans for crimes committed during California`s colonization by European Christians, Zee News reported.

Serra was accused of forcing many indigenous people to live in slave-like conditions in Catholic missions and of helping to destroy their languages and culture.