
Historically, German was spoken by communities throughout Pennsylvania. The German speakers were separated into the Fancy Dutch (Lutherans etc) and the Plain Dutch (the old order Amish and Mennonites). The Fancy Dutch assimilated and adopted English, leaving only the religiously conservative Plain Dutch speaking German today
A number of German Jews also moved into these communities. The oldest Ashkenazi Synagogue in the country was founded in Easton, Pennsylvania in 1761. The next was founded in Philadelphia in 1795. There’s a synagogue in Honesdale built in 1856. The synagogues in Charlottesville Virginia (1882) and Cumberland Maryland (1865) were built as German Jews moved into these communities Shenandoah valley along with Pennsylvania German Protestants.
But as more people moved into New York the Dutch community assimilated and Dutch culture largely disappeared. For modern Dutch-American culture (though probably not too much language) you’d want to go to Pella Iowa or Holland Michigan. The Dutch speakers in Iowa were negatively impacted by a World War One-era state ban on all non-English languages.