The rise in right-wing extremist offenses has become a significant global concern, particularly in the United States. These offenses are usually fuelled by radical ideologies such as nationalism and white supremacy, and have quadrupled over the past decade. Our analysis reveals that far-right extremist offenses in the U.S. have surpassed violence previously linked with jihadist-groups, with right-wing factions responsible for over 60% of extremist-related casualties since 2014. Moreover, the increase in these offenses is strongly corelated with a rise in immigration influx and demographic changes. This study employs a systematic literature review guided by the PRISMA framework and synthesizes relevant works to explore the relationship between rising immigration rates and the increase in right-wing extremist offenses. While the study mainly draws on intergroup threat theory, other sociological and psychological frameworks are also presented to shed light on how economic downturns and demographic transitions can provoke hostile right-wing sentiments toward immigrants and minorities, often culminating in violent crimes. Our findings and analysis emphasize the need for comprehensive policy interventions which not only address the rise in extremist discourse but also curb those societal factors that contribute to their growth. Additionally, we examine the role of social media in disseminating extremist ideologies and suggest that immigration policy reforms can help mitigate xenophobic attitudes. Moreover, we also recommend that efforts to combat right-wing extremism should focus on promoting social inclusion, economic justice, and close monitoring of extremist organizations, both online and offline.