What is the mass migration of immigrants to the US during the 1840s EXCEPT?

The mass migration of immigrants to the US during the 1840s was primarily driven by factors such as the Great Famine in Ireland and political unrest in Germany. This period saw a significant influx of Irish and German immigrants, who sought better economic opportunities and refuge from hardship. The arrival of these immigrants greatly influenced American society, culture, and Demographics, contributing to urban growth and the development of new communities. This wave of migration also sparked tensions over issues like labor competition and cultural integration.