In this thesis, I sought to determine what language was used on the issue of immigration in the UK prior to the referendum on EU membership. This was accomplished via the use of a discourse analysis, which used the theoretical lense of securitization from the Copenhagen School of International Relations as constructed by Barry Buzan and Ole Wæver. Securitization is a discursive process by which a population accepts an issue as being a matter of security and in need of actions outside of the political norm. This is done via the promotion of a particular issue as an existential threat to something held dear, which is known as a referent object. The period of analysis for this paper is from 1 June 2015 to 23 June 2016 and includes 4 political party manifestos from the 2015 parliamentary election, 22 parliamentary debates, 30 pronouncements from the UK Home Office, and 240 articles from the Daily Mail/MailOnline/The Mail on Sunday (for which full citations can be found in appendix 1 and 2). My findings include several themes of securitization spread between these primary sources, such as: a consistent concern that the EU was a threat to UK border and immigration control, fear of eastern European immigrants (particularly of low skill), fear of a collapsing NHS and other social welfare services, fear of an inflating population and the effect immigrants are having on those projections, fear of asylum seekers being either economic migrants or potential terrorists, fear of immigrant criminality, and even a fear that the EU itself is at threat from the influx of refugees and migrants. These sentiments were spread between my units of analysis, but were most pronounced from a language perspective from articles in the Daily Mail/MailOnline/The Mail on Sunday. However, the actions proposed in the party manifestos of the Conservative and UKIP party called for actions which violated international norms and treaties, as well as domestic law, thus suggesting that a level of securitization had already taken place. Some of these changes were subsequently discussed and adopted in the course of parliamentary debates. The Home Office abstained from securitization language, but also served to provide guidance for and normalization of actions taken by the parliament that were outside normal political action. On a broader level, I wanted to use this analysis to gain a better insight into the way fear is used in political discourse. This analysis gave view into the way in which a general sense of societal fear can lead to laws that would not otherwise be possible in a more relaxed environment. I also found that the securitization of immigration was weaponized in an effort to persuade the public to vote ‘leave’ in the Brexit referendum.