Trace your Ellis Island ancestors into The Netherlands
With the information you find on an Ellis Island passenger list, it is usually possible to trace Dutch immigrants in The Netherlands - in many cases using online sources.
Let's have a look at Franciscus and Geertruida van Valkenburg. They arrived on Ellis Island on 18 April 1911, on the S.S. Rijndam, with their 3 years old son Franciscus. According to the passenger list (which you can find on the website of the Ellis Island foundation), Franciscus was 31 and born in Oss, his wife Geertruida was 33 and born in Mill, and their son Franciscus was 3 years old and born in Berchem. Their last residence was Berchem. Their contact address in The Netherlands was Geertruida's mother, Mrs Wagemakers, who lived in Oss. They were on their way to Geertruida's brother, G. Wagemakers, in New York.
I started by searching Genlias for a Valkenburg - Wagemakers marriage (watch out for the "van" prefix in Dutch names - see my common pitfalls article). I had no problems finding what I was looking for: Franciscus van Valkenburg, born Mill en Sint Hubert, and Geertruda Johanna Wagemakers, born Oss, married 1 May 1906 in Oss. Their parents are Johannes van Valkenburg and Johanna Gommers, and Justinus Wagemakers and Geertruida de Groot.
Mill and Oss are in the province Noord-Brabant, so I also searched the main database at BHIC, where I found the birth of Franciscus: Franciscus van Valkenburg, born 9 July 1879 in Mill, son of Johannes van Valkenburg and Johanna Gommers.
Note that the Ellis Island passenger list has the birth places of Franciscus and Geertruida reversed.
For the marriage of Johannes van Valkenburg and Johanna Gommers I searched Genlias again, and I found: Johannes van Valkenburg, born 10 October 1839 in Oss, and Johanna Gommers, born 9 March 1848 in Sambeek, married on 3 May 1878 in Oss. Their parents are Francis van Valkenburg and Hestriena van Rosmalen, and Antoon Gommers and Catharina Lemmens.
There is more information on Johannes and Johanna on Genlias and BHIC, but let's continue with Johannes' parents. Their marriage is also on Genlias (and BHIC), but it took me a bit longer to find it, because the bride's name was spelled differently: Francis van Valkenburg, born 26 November 1812 in Oss, and Henrica van Roosmalen, born 9 March 1810 in Heesch, married 28 June 1834 in Oss. Parents are Johannes van Valkenburg and Maria van Straalen, and Antonie Petrus van Roosmalen and Maria van Grunsven.
We're getting close to 1811, the year the civil register was introduced. Online Dutch genealogy before 1811 is a lot harder than after 1811 (though certainly not impossible). The marriage of Johannes van Valkenburg and Maria van Straalen (taken from the church books) is on BHIC, but the parents are not listed anymore: Joannes Johannes van Valkenburg and Maria Francisci van Straales married on 5 April 1790 in Oss. Witnesses were Gijsbertus Ruijs and Joanna Gijsberta Ruijs. Johannes and Francisci were probably patronymics, which means their fathers were probably Johannes van Valkenburg and Franciscus van Straales (or Straalen?). That gives us a clue when we want to find the next generation, but I will not do that for this article.
So, starting with a listing on an Ellis Island passenger list, we were able to add three generations in the main line (Johannes, Francis and Johannes), and well over a century, all with freely accessible online resources!
There is a lot more information on Genlias and BHIC (and possibly other sites), also on siblings and, of course, other lines, but I leave that as an exercise for the reader.
There are more examples on tracing Dutch Ellis Island immigrants into The Netherlands in my article Trace your Ellis Island ancestors into The Netherlands and in the latest Trace your Dutch roots newsletter.