In Europe, linguistic diversity is a fact of life. Languages are an integral part of European identity and the most direct expression of culture. In an EU founded on the motto ‘United in diversity’, the ability to communicate in several languages is an important asset for individuals, organizations and companies (Kużelewska, 2014). Languages are also fundamental for respecting cultural and linguistic diversity in the EU (Károly, 2008). This paper will comprehensively discuss the language policies and language rights mainly in the Context of EU and how language diversity raises questions on those entitlements.
As a multilingual organization, the European Union has had to deal with the question how to accommodate the linguistic diversity existing within its borders (Ammon, 2006). It has responded to that challenge by affirming that linguistic diversity is a constitutional value that the EU institutions intend to ‘respect’. This commitment is now contained in a very prominent place of the EU Treaties, namely in Article 3, paragraph 3, of the Treaty on European Union (TEU), as well as in Article 22 of the EU Charter of Fundamental Rights (Leech, 2017). This constitutional mandate is reflected in policies that relate both to the operation of the European Union itself (including its relations with the citizens) and to the linguistic policies and rules of its member states (Arzoz, 2007).
These EU policies have encompassed the development of a number of language rights under EU law; essentially, these are (a)  the right to use any of the official languages of the European Union when dealing with its institutions; (b)  the right of European Union citizens not to be discriminated on account of the language they speak; and (c)  the right to interpretation and translation in criminal proceedings (De Witte, 2018).
References
Ammon, U. (2006). Language conflicts in the European Union: On finding a politically acceptable and practicable solution for EU institutions that satisfies diverging interests. International Journal of Applied Linguistics16(3), 319-338.
Arzoz, X. (2007). The nature of language rights. JEMIE6, 1.
De Witte, B. (2018). Language Rights and the Work of the European Union. In Language Policy and Conflict Prevention(pp. 221-230). Brill Nijhoff.
Károly, A. (2008). Language policy in the European Union. Eger Journal of English Studies8, 125-141.
Kużelewska, E. (2014). Unity in diversity. The language policy of the European Union.
Leech, P. (2017). European policy on multilingualism: unity in diversity or added value?. Cultus, 27.