I actually knew the answer to this question as soon as I saw it on Randy Seaver's Saturday Night Genealogy Fun post tonight!
Here is your assignment, should you decide to accept it (you ARE reading this, so I assume that you really want to play along; cue the Mission: Impossible! music!):
1. Which of your ancestors was the LAST immigrant to your current country? When did they arrive? Where did they arrive? Why did they migrate?
2. Write your own blog post, or leave a comment on this post, or write something on Facebook.
My most recent immigrant ancestor is on my mother's side. All four of my great-grandparents on her side were immigrants, coming to the United States between 1905 and 1911. The last one to arrive was my great-grandmother Minnie Zelda (Nowicki) Meckler (about 1880–1936). She was born in the Russian Empire, probably in Porozowo, which is now in Belarus. She departed Antwerp October 14, 1911 on the Vaderland with three young children in tow and arrived in New York City on October 23.
She came to this country because her husband, my great-grandfather Morris Meckler, had immigrated earlier, in 1906. The family was separated for five years. They came primarily for economic opportunity. Other family members had come earlier to pave the way.
As far as I currently know, on my father's side my most recent immigrant ancestor was my great-grandmother Jane Dunstan (1871–1954). She was born in Manchester, England. She departed England October 8, 1890 on the Lord Olive and arrived in Philadelphia on October 21. As far as I can tell, she was traveling by herself.
Less than a year later, on September 2, 1891, she married Thomas Kirkland Gauntt in Greenland, New Jersey (although I don't know if it was the Greenland that is part of Magnolia in Camden County or the one that is part of Edison in Middlesex County). Their first child, Frederick Cleworth Gauntt (named for Jane's father), was born a mere four months later on January 7, 1892. My grandmother was their second child, born a year after her brother, on January 14, 1893.
I have never heard any story within the family of why Jane came to the United States, but her brother Frederick Dunstan (1868–1932) came here first, about 1888 (I still haven't found a passenger list for him). Maybe he made New Jersey sound absolutely wonderful, and Jane just had to come. Or since she hooked up with my great-grandfather relatively quickly (apparently at the latest by about April 1891, only roughly six months after she arrived), maybe Fred was being a matchmaker?
I will say, however, that I still have not identified the biological father of my paternal grandfather, and while I have a good candidate, who was a native of New Jersey, it's possible that Grampa's biological father might have been an immigrant and might have arrived later than Jane did. The latest he could have arrived would be about July 1902, as my grandfather was born in April 1903, so my most recent immigrant overall would still be on my mother's side.