Communication is a key factor in every society, as it is an important part in every country. Moreover, the communicative power of politicians is influential and mainly based on their persuasive use of words in political speeches. One of the most essential political figures in the 20th century was Sir Winston Leonard Spencer Churchill (1874-1965), whose speeches are among the most important and influential documents depicting events in the early and mid-20th century. The textual analysis of Churchill’s speeches, crucial evidence to understand the WWII, shows several linguistic units that are important for the act of communication. In addition to this, these linguistic patterns include syntactical, lexical and stylistic levels that every translator, linguists, and politics students need to know. Sir Martin Gilbert (1936-2015), British historian and one of Churchill’s most prolific biographers, compiled a good deal of Churchill’s speeches and fragments whose communicative orientation needs to be remarkably mentioned. The aim of this study is to analyse 200 extracts from his speeches, summarised and selected in Gilbert’s The Power of Words (2012), and establish those models that may be difficult for translators. The methodology gives importance to the powerful words included in all his speeches, which turned into vital documents to understand the British and world history from a diachronic perspective. This methodology is based on the analysis and further comments of the terminological, syntactical and register levels used in all the fragments included in the book. These powerful words are essential communicative tools in order to understand the diachronic evolution of Churchill’s speeches, from his youth to his last speeches in his lifetime: terminology, syntax, and register as three important columns of every speech. Additionally, translators may deal with the evolution of the Churchillian speeches in his lexical and syntactical choices in order to reflect the increasing power of words. These speeches need to be translated from English into Spanish with several translation techniques. Thanks to this, we may reach certain conclusions: lexical and syntactical characteristics that led to a powerful use of words. As a result of these characteristics, this study shows the communicative techniques Sir Winston Churchill used in his speeches in order to fulfil his expectations in one of the most delicate periods in modern history. Therefore, this research includes its linguistic features as well as Sir Winston Churchill’s communicative tools in order to move the audience. These two main aspects will be therefore considered by linguists and translators in order to establish certain translations techniques to reflect those communicative purposes. To sum up, these conclusions may establish certain links in order to teach Churchill’s communicative power to translators or linguistic experts.