9,000 Converted to Catholicism in Brooklyn: That was in 1891

“Thousands at a Mission: The Work Which Paulist Fathers Have Been Doing In Brooklyn Interesting Services in the Church of the Sacred Heart. Many Total Abstinence Pledges Signed. The Renewal of Baptismal Vows—Conversions to Catholicism"

During the mission a large number of Protestants were converted to Catholicism. Last Monday night Bishop Loughlin confirmed them in the church. Several hundred children also received confirmation. The missionary fathers were highly pleased with the success of the mission. They said last Sunday that the surprisingly large attendance of men was particularly gratifying.

The Brooklyn Eagle, February 15, 1891 [Read the whole story in  McNamara's Blog]