The Kačić Oath — Uncover the Pirate Dukes' Secret Pact

Omiš becomes in the 13th century the stronghold of the Kačić family, local lords who transform this natural Dalmatian port into a formidable corsair base. Mladen Kačić, first documented duke around 1200-1260, establishes his headquarters on the heights where Mirabella fortress stands today, built 107 meters above sea level to monitor galleys ascending the Cetina river. The old port, with its 1-kilometer-long quays, becomes the anchoring point for raids that will terrorize Venice and Adriatic merchants for three centuries.

Mirabella fortress, erected in the 13th century by the Kačić, still dominates Omiš landscape from its 107-meter altitude. Restored in 2006, it now houses one of Europe's smallest open-air theaters, but its stones preserve memories of war councils where attacks against Venetian convoys were planned. Ninus Kačić, corsair chief of the late 13th century, allegedly sealed alliances with other Dalmatian pirate clans here, creating a maritime terror network extending from Split to Dubrovnik.

In the 15th century, facing growing Venetian and Ottoman threats, the Kačić build Fortica fortress at 273 meters altitude, accessible via a 1.5-kilometer trail from the port. This multi-hectare citadel, with its 500-meter-long ramparts, becomes the last bastion of Kamjen Kačić, last independent duke of Omiš around 1320-1370. From these strategic heights, lookouts scan the Adriatic horizon and alert galleys hidden in Cetina's coves.

Saint Peter's Romanesque church, built in 950 and one of continental Dalmatia's oldest, becomes the personal sanctuary of the Kačić dukes. Its single nave and 12th-century Romanesque bell tower shelter ex-votos deposited by corsairs after naval victories. Omiš museum, opened in 2006 in a former 15th-century palace belonging to the Kačić, now preserves artifacts from this era across 300 m² of exhibition space: weapons, marine charts and documents about the mysterious 'pact' binding the corsair dukes together.

Your journey through Omiš reveals how a Dalmatian lordly family built a corsair empire that challenged Venice for centuries. From Mirabella fortress to Fortica's ramparts, from old port quays to Saint Peter's vaults, you take away understanding of a unique maritime feudal system in the Mediterranean. Omiš stones still tell the story of these pirate dukes who transformed a small Cetina port into the capital of Adriatic privateering, leaving a legacy celebrated annually at the Pirates Festival since 1999.