The second half of the nineteenth century saw the greatest mass migration of European population since the middle ages. The first wave, initiated mostly by the US' western expansion and the (in)famous Californian gold rush, brought millions of migrants from western and northern Europe to America's doorstep. Nearing the end of the century, the mass migration wave moved eastward – towards eastern and southeastern Europe. As a part of the region's biggest and most powerful state, Austro-Hungarian Monarchy, the Kingdom of Croatia-Slavonia became somewhat of a hotspot for emigration to the United States. Pressured by its demographic transition, unsure political climate, and, most of all, a dire economic situation due to the general absence of industrialization and modernization – many Croatian and Slavonian citizens fled across the Atlantic. With or without the involvement of travel or emigration agents and agencies, they boarded gigantic ocean liners and traveled predominantly in third class, located below deck. Upon finally reaching North America, they were questioned and examined at Ellis Island. Some immigrants were sent back to Europe, but most entered the USA where they faced new challenges. After days and weeks of traveling in unsanitary conditions, now they often lived in unsanitary conditions, did the worst and lowest paying jobs, and often stayed in sub-par accommodation. Some died working in dangerous conditions, and some returned to their homeland, defeated by their American fate. Yet, most stayed, and in one way or another – prospered. Most emigrants from Croatia and Slavonia were temporary migrants who moved to America in search of relatively swift profit, for the purposes of modernizing or expanding their rural estates. Those migrants returned to their villages, where they were often hailed as heroes. Those who decided to stay in America worked, survived, and eventually started organizing into fraternal unions and other organizations, such as the Croatian fraternal Union. They maintained transatlantic connections with their friends and families and nourished multiple aspects of Croatian culture and tradition. Additionally, even those who stayed in America became a source of highly necessary financial support to their native land, in form of emigrant funds which considerably boosted the home economy. Despite the efforts to regulate transatlantic migration from both Austria-Hungary and the USA, the sole event that had the power of finally „closing the floodgates“ was the First World War with the restrictions it posed. Today, even though many of Croatia's emigrants were completely assimilated, a transatlantic bond exists, in different forms and from various sources.