The following map of Krajina appears in the book "Yugoslavia - A Country Study" issued by U.S. Government Printing Office, Headquarters - Department of the Army, Edition 1992, page 14.
In case you can not read the text associated with the above map here it is:
SOURCE: Based on information from United Kingdom, Admiralty, Naval Intelligence Division, Yugoslavia, 2: History, Peoples, and Administration, London, 1944, 20.
Figure 2. Military Frontier Province Between the Habsburg and Ottoman Empires, ca. 1600-1800.
Notice the size of "Croatia" vs. "Military Frontier Province" (i.e. Krajina). Also notice that "Slavonia" and "Dalmatia" are different entities then Croatia. Croatian Communist Tito renamed all those areas into - Croatia.