Question: In the [מטה אשר](http://hebrewbooks.org/pdfpager.aspx?req=35269&st=&pgnum=12) (commentary to שמלה חדשה), it is recorded that it was the custom of Jews in "מדינות מלכות רוסיא וגאלציא וגם במדינת הגר בקהילת היראים" to use the sefer שמלה חדשה to learn the halachos of shechita. So I figured out (big deal) that רוסיא is Russia, and גאלציא is Galicia; but what/where is הגר?

Answer: 
Hungary.

See this matzeva from Sighet, Hungary

<http://books.google.com/books?id=MF8LAAAAIAAJ&pg=PP11&lpg=PP11&dq=%22%D7%9E%D7%93%D7%99%D7%A0%D7%AA+%D7%94%D7%92%D7%A8%22&source=bl&ots=XTrztOSUE_&sig=99MotorIcpDDGH2q2_SjH6ao6Zo&hl=en&sa=X&ei=rSdnU7jhKbK0sQS15IHQCw&ved=0CC0Q6AEwBDgK>
Yoni beat me to it, but I found a source if you'd like one: the Targum on Tehillim 83:7 translated "הגרים" as "הונגראי". 

The term is used so often all over Jewish literature to refer to Hungary though that a source isn't really needed. (In fact, the translation offered by Targum there is highly unlikely to be correct; just thought it was a cool tidbit)