This paper analyzes the way the Republic of Dubrovnik attained the region of Konavle under their rule while specially focusing on economic, political and military aspects of the city of Cavtat, the fort Sokol and the town of Molunat. The paper briefly explains the earliest history with a particular focus on the construction and development of fortifications in the aforementioned places. In doing this, the paper also connects the fortifications with the three main aspects and the decisions of the authorities in Dubrovnik. The development of fortifications of Cavtat is studied from the year 1427. and the arrival of the city under the rule of the Republic of Dubrovnik, especially focusing on the war events related to Radoslav Pavlović from the year 1430. and Stjepan Vukčić Kosača from the year 1451. The development of fort Sokol is also studied in detail from the time of arrival under the rule of the Republic to the end of the 15th century, when major improvements to the fortress were completed. The charter by which Sokol comes under the rule of the Republic is especially emphasized, as well as the safe haven at the base of the fort, called „Kamen“ or „Pod Kamenom“. The development of Molunat i studied from 1430., when the construction of the first walls began, to 1468. when the second walls were being constructed. Simultaneously, the actual defensive role of the first walls is subjugated to consideration and the defensive role of the second walls is confirmed. Ultimately, the paper also briefly analyzes the issue of fortified administrative and residential complexes, primarily the duke's palace in Pridvorje.