Johannes Lucius (Croatian: Ivan Lučić; Italian: Giovanni Lucio; September 1604 – 11 January 1679) was a Dalmatian historian, whose greatest work is De regno Dalmatiae et Croatiae ("On the Kingdom of Dalmatia and Croatia"), which includes valuable historical sources, bibliography and six historical maps.

His first book Vita B. Ioannis confessoris episcopi Traguriensis et eius miracula [Life of St. John the Confessor, Bishop of Trogir] (1657) is an important source of Croatian, and especially Dalmatian, history between 11th and 13th centuries.

In addition to his many other historical works, Lucius also engaged in archaeology, geography, mathematics, physics, astronomy, construction and studying of ancient Christian monuments, Roman mosaics and inscriptions.

In his book Lucius pointed out the difference between the Romance and Slavic Dalmatia, the habits of the people and the cultural borderlines.

Lucius showed them that their roots reached back to the famous medieval dukes of Šubićs noble family from Bribir.

Lucius participated in the dispute about the authenticity of the text of Trimalchio's Banquet by the Roman satirist Petronius, which had been found in Trogir.

Johannes Lucius was the first Dalmatian historian who critically examined and used historical sources: documents and chronicles, inscriptions and last wills.

His numerous letters, revealing him as a man of integrity and a skillful writer are a valuable fresco of the conditions of his time.

Lucius' work, written in a lapidary and clear style, based on critical considerations, is the cornerstone of the modern historiography about Dalmatia.