Political map of Europe & the Mediterranean 8 August 106 (Second Dacian War): Despite his treaty with Rome, King Decebalus of Dacia (Kingdom of Dacia) maintained a policy of rearmament and expansion, attacking the Roman client kingdom of the Iazyges in around 104. By 105 Trajan had had enough and invaded Dacia with a large army (Second Dacian War), conquering and annexing (Roman Dacia) the kingdom the following year.