Geographical proximity and the gravitation of Italian regions towards the Adriatic Sea, along with the ecclesiastical and political tendencies of Croatia towards the West, dictated, in spite of many mutual prejudices, common connections through the centuries, which were particularly fruitful in the era of the Venetian Republic, and intensified through Humanism and the Renaissance, when the civilisational levels of the opposite Adriatic shores drew closer together. Early links were noted in the Codex aquileiensis, a 5th or 6th century codex of the Gospels in Latin, signed in the margins during the centuries which followed by prominent pilgrims, among whom were the Croatian dukes Trpimir, Branimir and Braslav, while Dante Alighieri mentioned a devout Croatian pilgrim in his Divine Comedy. His efforts were rewarded by four translations of the entire work and a further two versions of Inferno into Croatia.
As the key language of international communication and literacy, Latin remained for a long time the second language of Croatian culture, making Croatia part of the wider European cultural scene, through the Latinist school. Later, Italian became the language not only of culture, but of part of the coastal population, and its influence was in no way diminished by the strengthening of Austrian power in the Adriatic after the fall of Napoleon (1815). Links between northern Croatia and Italy were somewhat fewer than on the coast, but were never completely severed, while the Italian influence was felt via continental routes, particular through Vienna.
From the earliest contacts, whether religious, commercial, or cultural, education played an important part in linking the two coastlines, through universities and the Italian towns. The most prominent role belonged to the University of Padua (1222), where many Croatian intellectuals studied; the humanists Jan Panonac (Ianus Pannonius) and Juraj Šižgorić, the philosophers Juraj Dragišić and Frane Petrić (Franciscus Patricius), the natural historians Federik Grisogono, Faust Vrančić, Markantun de Dominis and Marin Getaldić, and others, whose renown and achievements reached European proportions. An important role was played by institutions for educating clergy with roots in the Croatian lands; the Croatian Papal Institute of St Jerome in Rome (1787), the Croatian Institute in Bologna (1553–1781) and the Illyrian Colleges in Loreto (1580–1860) and Fermo (1663–1746).
The main spiritual trends in the Croatian lands (artistic styles, philosophical and scientific movements) were closely linked with Italian counterparts (Pre-Romanesque, Romanesque, Renaissance, Baroque, the Reformation and Counter-Reformation, etc.). Some of these trends affected national awareness in Croatia in key ways; modelling itself on the Italians, Croatian as a national language (instead of Italian and Latin) was raised to a literary level, whether through a multitude of translations (Marko Marulić, Šiško Menčetić, Marin Držić, Stijepo Đurđević and others) or through original works in Croatian, which led to the rapid growth of Croatian literature in the Renaissance and Baroque periods. This was particularly evident in Dubrovnik, which, although an independent republic, had ongoing links with Italy. Writers in Dubrovnik and Dalmatia had a wide knowledge of Italian authors, while their poetic models were Francesco Petrarch (Petrarchism), Pietro Bembo (Bemboism), Jacopo Sannazaro, Ludovico Ariosto and Torquato Tasso, whose pastorale Aminta was published in Croatian as Gliubimir by Dominko Zlatarić in Venice in 1580, a year before the Italian original.
The academies became the centres of cultural life in the 18th century, communities of educated people who nurtured stylistic simplicity in contrast to Baroque excesses. Following the lead of the Accademia degli Arcadi in Rome (1690), among whose founders were two Croats, Nikola Radulović (who later became a cardinal) and Stjepan Gradić, the Director of the Vatican Library, similar institutions were founded in Croatia, as in the rest of Europe, such as the Accademia degli Oziosi Eruditi in Dubrovnik and the Accademia degli Incaloriti in Zadar, where Ivan Tanzliger Zanotti, compiler of a Croatian-talian-Latin dictionary and translator of Vergil's Aeneid, was active.
From the 19th century on, Italian influence in Europe gradually diminished, but the effects of contemporary Italian authors continued to be marked in Croatian culture and beyond, although its continental elements became on the whole oriented towards Austrian and German art. The proponents of the Croatian Revival (Petar Preradović and Ivan Mažuranić) found in Italy an ideal for the unification and independence of their homeland. At that time, the writer and philologist Niccolo Tommaseo, born in Šibenik, came to prominence, as he brought the 'Illyrian spirit' to Italy, although he later parted company with the Illyrianists, as he opposed the unification of Dalmatia and Croatia, and even more so the unification of Dalmatia and Italy, which he maintained should never extend in the north beyond the 'arc drawn by the compass' (i.e. as far as Istria, no further).
In the 20th century, mutual contacts were based on the increasing level of translation activity; in Croatia, Italian classics were translated, while Croatian literature was presented to the Italian public primarily by author/translators such as Ivo Vojnović, Milan Begović and Vladimir Nazor, but also by Italian experts in Slavic studies, particularly after the foundation of chairs in Slavic Philology. Italian writers with dual affinities (Italian and Croatian) were also preoccupied with Croatian themes – such as Enzo Bettiza and Fulvio Tomizza – whose poetry of coexistence and tolerance, the so-called 'Romanticised dialogue' was accepted by writers on both sides of the Adriatic (Nedjeljko Fabrio, Mario Schiavato, Claudio Ugussi and others), and even by Silvio Ferrari, the most competent translator of Krleža's works. Finally, the gap between the two coasts was bridged by Predrag Matijević, Professor of Slavic Studies at La Sapienza in Rome, and the author of the Mediterranean Breviary, particularly popular in Italy, and translated into many languages.
Contemporary cultural links have been regularly maintained thanks to national minorities, mainly the Italian minority in Croatia but, in recent times, also by the Croatian minority in Italy (the umbrella organisation is the League of Croatian Communities in Italy, founded in 2001). On the other hand, open borders have led to the free flow of information and people, and many personal, cultural and scientific contacts and exchanges. Affirmed Croatian Romanists have contributed greatly to this (Josip Jernej, Pavao Tekavčić, Vojmir Vinja, Žarko Muljačić, Mate Zorić, Mladen Machiedo, Mirko Tomasović), while the Italian Cultural Institute in Zagreb (founded in 1942) has kept up regular activities since 1973.
Although the prevailing characteristic of the influence of Italian culture in Croatia has mostly been in the area of mutual relations, Italian art has nonetheless found one of its greatest advocates in Croatia, while the gravitation of Italy towards Croatia, particularly the coast, has left its mark on the Italians. Apart from the fact that Croatian writers have participated in Italian cultural events, several Italian writers have dealt with Croatian themes and concepts (Dante, Niccolo Machiavelli, T. Tasso and others), as have historians (the monumental Illyricum sacrum by Filippo Riceputi, Daniele Farlati and Jacopo Coleti) and printers (up to the late 18th century, Venice was the centre for publications in Croatian), while travel writers have contributed to a wider knowledge of the Croatian lands (Benedetto Ramberti, then the renowned Alberto Fortis, Giovanni Battista Casti, and others). Furthermore, the circulation of people and artistic works between Croatia and Italy over many centuries has not been limited simply to culture, based on language, but has incorporated civilisation in general, and spread to the fine arts, music, theatre, philosophy, architecture, etc. In recent times, it has also spread to film, comics and design. Many Italians (teachers, artists, representatives of ecclesiastical and political powers, those in holy orders, doctors, notaries, chancellors, craftsmen and traders) have also infiltrated areas of Croatia, by participating in and influencing cultural life, while many Croats (Schiavoni) have played an irreplaceable role in Italian and European cultural circles (such as the scholars F. Petrić and Ruđer Bošković, painters Julije Klović (Guilio Clovio Croata) and Federiko Benković (Federico Bencovich Schiavoni), sculptors Franjo Vranjanin (Francesco Laurana), Ivan Duknović (Giovanni da Trau) and Ivan Meštrović, and architect Lucijan Vranjanin (Luciano Laurana) along with many others.