How do I find out more about my Dad? He was born in 1895 and passed away in 1972. I am not sure if he is from Austria or Croatia! HELP!!!
Go to ancestry.com. I think they have a two week free trial.
The various census have a column for where you were born.
Ancestry also has a lot of immigration information.
It’s a start.
Look for writing from his lifetime that includes tons of unnecessary !'s. I hear they are genetic 
If he was born in Croatia, there’s a chance he was recorded as being from Austria:
It’s nice to mark PDFs.
Could you be a little more specific about what you are trying to find out about your dad?
Do you know some basics like what his name was? Do you know whether he ever left Austria or Croatia? If so, where he lived? Do you know where he died? How basic is the information you are looking for?
Another web site to search is https://www.familysearch.org/ This is the family search site run by The Church of Jesus Christ of Latter-day Saints, but they provide it for free and is quite useful.
I will echo the previous posters, that if you are looking for such information, you should list everything you know. When did he immigrate, when and where was he married? etc. If you know when he immigrated, that might lead to the ship and manifest,
http://www.ellisisland.org/ is another resource, if your father came through Ellis Island.
The best strategy is of course finding the oldest relative, and ask them to tell stories, if possible.
My grandfather on my father’s side is from Lithuania and is listed that way on some census forms and is listed as being from Russia on others.
Where were you born? Did your father immigrate to the US, Canada, or some other country? If he did, his immigration records might indicate where he was from. Where did he get married? Are there records? A marriage license might indicate place of birth. Did he apply for citizenship somewhere? A naturalization certificate or application form might indicate country of birth or prior citizenship that might give you some information. What about your own birth certificate? My own birth certificate not only indicates where I was born, but where my parents were as well. Everyone who looks at my birth certificate can tell that my mother was from New Jersey, therefore I am from New Jersey too (Cartman 2010), although I am not a Jew or Ginger.
Do you have any other relatives you can ask? Can you call up your aunt and ask her if she remembers where her brother was born?
Anecdote time. I tracked down some legal documents that had been written by a great-great-great grandfather and was allowed to take a look at them. His handwriting looked very familiar, almost as if I was looking at something I had written myself.
People self-identified their homelands when the census takers visited. Part of my family came from a German speaking part of far western Hungary that became part of Austria only after 1918 (under the Dual-Monarchy system, they were Hungarian subjects). Most of my ancestors from this part of my family identified their homeland as “Austria” in the census, though a few were more accurate and said “Hungary”. The 1930s census for one asks for the birthplace of the person’s mother and father and at this point, the range of answers amongst the children of those immigrants gets really interesting, almost no one identified their parents’ birthplace as Hungary, most did as Austria, and a few said Germany (the Anschluss was still in the future).
I very much appreciate a few other ancestors who identified particular pre-1918 German principalities instead of just “Germany”… that makes hunting them down in the “old country” somewhat easier!
There’s also the chance that the census taker didn’t quite understand their accent and just wrote down a guess (this guy sounds German… so Germany must be it!).
Familysearch is a stripped-down version of ancestry.com, but it’s very good when you’re looking for basic information.
Type in your father’s name and see what comes up. You can narrow it down by location and year.
Ancestry.com can sometimes identify people with a name, approximate birth year, and the name of one city that they lived in. On the other hand, some people just don’t show up in many lists.
If you hit the jackpot, he’ll be identifiable AND listed in a few other people’s registered family trees. You’ll suddenly, BAM, have RELATIVES!
(My Grandma added CAPITALS, large fonts, underlines, and squiggly underlines to her exclamation marks. I thought I’d indulge in my heritage.)