Which religious group featured in the film 'Witness'?

Witness is a 1985 American thriller film directed by Peter Weir and starring Harrison Ford and Kelly McGillis. The screenplay by William Kelley, Pamela Wallace, and Earl W. Wallace focuses on a detective protecting a young Amish boy who becomes the target of a ruthless killer after he witnesses a brutal murder in Philadelphia's 30th Street train station.

https://en.wikipedia.org/wiki/Witness_(1985_film)

Some of the film 'Witness' was shot on location in Intercourse and Strasburg, Pennsylvania (known as 'Amish country'). Members of the Amish worked as carpenters and electricians on the film set but weren't prepared to appear on film, so the Mennonite community provided a lot of the film's 'extras'.

The Amish church is an offshoot of the Mennonite church, resulting from a doctrinal schism in 1693.

Although some of the dialogue in the film uses the Pennsylvania Dutch which is typical of the Amish, most of the non-English portion of the script uses untypical High German.

When the film was released it was rejected by the local Amish community, and the National Committee for Amish Religious Freedom called for a boycott, concerned at inaccuracies and also at what the film would contribute to encouraging tourist 'sightseeing' of Amish communities.

https://en.wikipedia.org/wiki/Witness_%281985_film%29

https://en.wikipedia.org/wiki/Mennonite

https://en.wikipedia.org/wiki/Amish