Here's a taste:
One of the most momentous cases on the Supreme Court docket as war raged globally in 1943 was about a single sentence said aloud by schoolchildren every day. They stood, held their right hands over their hearts or in a raised-arm salute and began, "I pledge allegiance to the flag…" To most Americans the pledge was a solemn affirmation of national unity, especially at a time when millions of U.S. troops were fighting overseas. But the Jehovah's Witnesses, a religious sect renowned for descending en masse on small towns or city neighborhoods and calling on members of other faiths to "awake" and escape the snare of the devil and his minions, felt otherwise. They insisted that pledging allegiance to the flag was a form of idolatry akin to the worship of graven images prohibited by the Bible. In West Virginia State Board of Education v. Barnette, Walter Barnett (whose surname was misspelled by a court clerk) argued that the constitutional rights of his daughters Marie, 8, and Gathie, 9, were violated when they were expelled from Slip Hill Grade School near Charleston, W.Va., for refusing to recite the pledge.You can read the rest here.
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Jehovah's Witnesses were unlikely champions of religious freedom. The sect's leaders denounced all other religions and all secular governments as tools of the devil, and preached the imminence of the Apocalypse, during which no one except Jehovah's Witnesses would be spared. But their persistence in fighting in the courts for their beliefs had a dramatic impact on constitutional law.
hat tip: bookforum