Braslav or Bräslav was the last duke or prince (knez) of Pannonian Croatia

Pannonian Croatia

Pannonian Croatia was a medieval duchy from the 7th to the 10th century located in the Pannonian Plain approximately between the rivers Drava and Sava in today's Croatia, but at times also considerably to the south of the Sava. Its capital was Sisak...

 (Southern Pannonia, Transsavian Croatia) in 880-898/900 vassalaged to the Kingdom of East Francia. The territory he was responsible for was extended by the Franks to include the territory of the former Principality of Lower Pannonia (frequently called just "Pannonia" by Frankish texts) in 896.

Braslav fought against his Slavic neighbour, the Great Moravia

Great Moravia

Great Moravia was a Slavic state that existed in Central Europe and lasted for nearly seventy years in the 9th century whose creators were the ancestors of the Czechs and Slovaks. It was a vassal state of the Germanic Frankish kingdom and paid an annual tribute to it. There is some controversy as...

n king Svatopluk I

Svatopluk I

Svatopluk I or Zwentibald I was the greatest ruler of Moravia that attained its maximum territorial expansion in his reign . His career had already started in the 860s, when he governed a principality, the location of which is still a matter of debate among historians, within Moravia under the...

 in the service of King Arnulf

Arnulf of Carinthia

Arnulf of Carinthia was the Carolingian King of East Francia from 887, the disputed King of Italy from 894 and the disputed Holy Roman Emperor from February 22, 896 until his death.-Birth and Illegitimacy:...

 of East Francia. The alliance against Great Moravia expanded when the newly-arrived Hungarians joined the fight on the Frankish King's side. After Svatopluk's death in 894, the Hungarians turned against the Frankish King, so King Arnulf gave the Principality of Lower Pannonia to Prince Braslav, seeking to save what could be saved from Hungarian pillages. Thereby, Braslav also became a ruler of the Carinthians living in present-day eastern-most Austria

Austria

Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...

 and around Ptuj

Ptuj

Ptuj is a city and one of 11 urban municipalities in Slovenia. Traditionally the area was part of the Lower Styria region. The municipality is now included in the Podravje statistical region...

. The fate of Pannonia could not be changed, as the Hungarians overran it in 900/901, thus ending Braslav's reign.