Bosnia

Bosnia was a country in Europe that had been part of former Yugoslavia. In the late 20th century it became torn by internecine conflict. Eve Waugh believed that Great Britain was capable of becoming like this country even without an alien invasion. (NA: The Dying Days) It was the country from which original vampire legends came, despite the popular belief that they came from Romania.

Sam Jones was reminded of news reports from Bosnia by the abandoned village of Lanzerath in December 1944. (EDA: Autumn Mist)

In September of 2009, it was one of the countries from which Ianto Jones found reports of all children stopping in a trance at 8:40 GMT. (TW: Children of Earth: Day One)

Behind the scenes

 * Conversation in The Dying Days shifts from Yugoslavia to Bosnia without explicitly stating that the two are connected. References don't even make it clear that it is a country not a city. Although later compared to Britain, Alistair Gordon Lethbridge-Stewart compares Bosnia to the city of Belfast and Ianto Jones' list of countries also includes the city of Tokyo.
 * The Tenth Doctor refers to a man who assassinated an Austrian archduke, starting World War I, as a Serbian. (DW: The Family of Blood) It might be more accurate to say that was a Bosnian Serb, Serbs being an ethnic group in Bosnia.