Short answers, pulled from the story.
Roman galleys sailed into the Adriatic Sea in 229 BC to confront pirates operating from the coast of modern-day Albania and Croatia. These forces fought three distinct conflicts against the kingdom of the Ardiaei during this period.
Gaius Vibius Postumus served as the military commander of Dalmatia under Germanicus in 9 AD. Velleius Paterculus wrote about this command in his compendium of Roman history.
Dalmatia fell under the praetorian prefecture of Italia Africa et Illyricum following the death of Constantine the Great in 337 AD. Constans removed Macedonia Dacia and Pannonia from that larger prefecture in either 343 or 347 AD to form a separate praetorian prefecture for those regions.
German historian Theodor Mommsen wrote that coastal Dalmatia and its islands were fully romanized by the 4th century. He claimed Latin-speaking populations dominated the region during this era while native Illyrian speakers continued to use their own language throughout rural areas.
Odoacer defeated Ovida and annexed Dalmatia to his kingdom of Italy after Julius Nepos was assassinated in 480 AD. Zeno sent Theodoric the Great to Italy four years later to remove Odoacer from power.