The Schwenkfelders are called after Caspar Schwenckfeld von Ossing, a Silesian Knight,and counselor to the Duke of Liegnitz, Prussia. Schwenckfeld was a contemporary with Luther, Zwingli and other Reformers, and had his adherents, who were tolerated by the German Emperors, in the arch-dukedom of Silesia, espcially the principalities of Taurand Liegnitz,for nearly two hundred years.
They, like many others, had to endure persecutions in 1590, 1650, 1725 when they were compelled to seek sheltor in Upper Lusatia, Saxony, under the protection of the Senate of Gorlitz, and of Nicolaus Ludwig Zinzendorg, who had them under his protection about eight years, when they resolved to emigrate and seek a home in Georgia, but on arriving in Holland they were persuaded to go to Pennsylvania. Some came over in 1733, but the greater part in 1734.
There is a slight discrepancy between the statement, in a German book printed 1771, giving account of the voyage and arrival of those imported in the ship Saint Andrew, and the original papers. From the book alluded to it appears the ship Saint Andrew, John Stedman, Master, was freighted with Schwenkfelders, followers of Caspar Schwenckfeld, born in Lower Silesia, 1490.
These left their homes in April 1734, embarked at Altoona, Denmark, May 14, arrived at Philadelphia September 22, and on the 23rd they declared their fealty: On September 23rd all male persons above the age of sixteen had to appear in the court House, in order to swear allegiance to the rules of the country, to wit: The King of Great Britain and His successors to the Crown of England.
Here it may be noted, that these were not the first Schwenkfelders in Pennsylvania. September 18, 1733, a number of them arrived at Philadelphia, in the brigantine Pennsylvania Merchant: among these were Johann Klemm, Gottlob Klemm, Georg Scholtz, David Scholtz.
It would appear thy remained for some time in Philadelphia. Mr. von Beck in his Reise-Diarium von Ebenezer in Georgia Nach den Nordlandern, under date, Philadelphia, June 6, 1734, says: "Here are of all denominations and sects: Lutherans, Reformed, Episcopals, Presbyterians, Catholics, Quakers, Dunkers, Mennonites, Sabbatarians, Seventh-day Baptists, Separatists, Bohemists, Schwenckfeldians, Tuchfeldtians, Eucthelists, Jews and Pagans, etc." - Ulsperger News, I, p 156.
On September 24 shortly after their arrival, they celebrated their first Gedaechtnisz Tag, the September Thanksgiving. Though fewer than 3,000 people in a handful of Pennsylvania congregations still observe it, it is the oldest continuous Thanksgiving tradition in America.
Schwenckfelder Passenger Ships:
Pennsylvania Merchant 1733
St. Andrew 1734
Source: A Collection of upwards of Thirty Thousand Names of German, Swiss, Dutch, French and other Immigrants in Pennsylvania From 1727 to 1776; Prof. I. Daniel Rupp, Second Revised Edition, 1876, Philadelphia.