Queen Marie of Yugoslavia...well...technically only by Dowedger. She was a Princess of Romania who married into the family. She Married King Alexander I who was the first King of a United Yugoslavia. His Father has been Serbian, and he was a big mover and shaker of the Serbian Army during the wars in the Bulkans which occured just before the Great War. He was very dictatorial in how he wanted Macedonia to be run.
The Kingdom of Croatia was next to be added to his list. Bosnia wasnt really Bosnia at the time I dont think
Anyway, his Government was a nightmare from the word go...with political backstabbing, and a murder, Alexander became so infuriated that in 1929 he basically became a dictator.
on a visit to the French Republic he was assassinated on live television by a disgruntled Macedonian. Thankfully Marie had been busy and had already given him a multitude of male heirs.
The result of all of this was quite dire, and well within the confines of the 1900s Yugolsavia had been formed from violence and completely dissolved by violence. Serbia, Croatia, Bosnia and Macedonia, were...were not...and then were again...and Marie saw the start of the were not...and thankfully died before seeing her Husbands work completely reversed