Under the Roman Empire and later the Frankish and Venetian Empires (as opposed to being under the Byzantine Empire), the region and people of Croatia always looked west and became Catholic while most of the people on the peninsula later converted to Eastern Orthodox. All these rulers were Catholic, including the later Hapsburgs, maintaining the Catholic faith of the people and truly giving them a different identity than the Serbs, Montenegrins, and Bosniaks, who speak a similar language.
These outside rulers also had great influence on the people of the region as architecture along the coasts is strongly Venetian and foods from both Italy and Austria can be easily found, although the natural reliance on the seas still dominates the cuisine.
Under Yugoslav rule Croatia changed greatly in terms of lifestyle, but didn't change to a significant degree culturally. Communism encouraged advancements in technology, communication, infrastructure, and transportation, which meant cities grew and jobs shifted to the industrial sector. For much of history life was based off the lands as many people farmed, raised animals, or fished; this is still true to a great degree, but today many others find work in other sectors.
Despite Yugoslav rule, the culture of Croatia remained tied to their past and little changed in this regard. The major differences between Croatia and their neighbors remained, beginning with Catholicism separating them from most neighbors while ethnicity and language continued to differentiate the people from Slovenia. However, more than these simple differences, the people of Croatia tend to focus on family, friends, neighbors, and the future; there is a push forward, constantly seeking out a better future, a stable economy, and greater opportunities, which seem to begin with attracting tourists to their beautiful islands, beaches, parks, and cities.