[note: below contains citations from KKK publications and references to anti-Catholicism]
In 1869 the religious issue in New York City escalated when Tammany Hall, with its large Catholic base, sought and obtained $1.5 million in state money for Catholic schools. (Wikipedia)This being the days of yore, the "religious issue" here is not Christian v. secular, but the older feud of Protestants v. Catholics. Here is more context:
Following the conclusion of the civil war Catholics began challenging the religious practices common in the public schools. Catholics, seeing the obvious evangelical Protestant overtones to public education, set up parochial schools and sought shares of the common school fund or exemptions from taxation. Additionally, Catholics challenged the practice of hymn singing, praying, and reading from the King James Bible in the public schools.
New nativist groups, such as the Order of American Union, the Alpha Association, and the American Protective Association, arose to do battle against the growing Catholic-immigrant menace. Not surprisingly, Congressmen and Senators found themselves subject to the attitudes and pressures of the times. One of the several measures proposed to deal with this controversy was the Blaine Amendment. (Green, 1992)Despite the Blaine Amendments, the Catholic Church continued to operate affordable, quality parochial schools. The Ku Klux Klan probably reached its peak in national influence and membership about fifty years later. By that time, the hot-button issue had moved from state funding of overtly religious schools to whether anti-Catholic majorities would allow parochial schools to continue to exist. Anti-Catholics condemned what they saw as demoralizing criticism of public (read: predominantly Protestant) public schools as an attempt by Catholics to poach students. Here is one commentary:
In Nebraska, Iowa, Illinois, Indian, Ohio and Pennsylvania the schoolhouses and equipment were found to be twenty-five to fifty years behind the times. In some of the buildings it would be impossible for the children to keep warm in cold weather as there was nothing between the ground and the floors to keep the wind out. The homes near these schools were often modern structures, up to date in every way. One can readily see how parents living in such homes are often induced to send their children to parochial schools, and why Rome is making such a desperate fight to discredit our public schools and to prevent any appropriation of money for their upkeep and advancement.
An enemy to public school is an enemy to the Constitution. We are thankful that a white-robed army has arisen, a might host that will put the Bible in the schoolroom and forbid the lecherous hand of popery to interfere with our free institutions. (Klansmen: Guardians of Liberty)The fascinatingly ignominious author of that opinion was Alma Bridwell White, who could add racist, antisemitic, feminist, first female American Methodist bishop, and Klan sympathizer to her anti-Catholic credentials.