Presidential Speeches are key instruments of political communication. They are powerful tools used to shape public opinion or set nation-level agendas as a presidential leader. Analyzing these speeches helps uncover the underlying ideologies, emotional appeals, and rhetoric strategies used by presidents to influence the perception of the government. This paper analyzes speeches delivered by the presidents of the United States of America from George Washington in the year 1789 to Donald Trump in the year 2020, using the U.S. Presidential Speeches Dataset from Miller Center. It presents a computational linguistic analysis of historical presidential speeches spanning from the late 18th century to the 21st century until January of the year 2020. Utilizing natural language processing techniques, we analyze various linguistic dimensions including lexical diversity, sentiment, rhetorical structure, thematic content, and ideological positioning. Our key findings reveal a gradual decrease of 5-10% in lexical diversity every decade and the strong use of repetition across contexts. In addition, we identified trends correlated with historical events, party affiliation, and changing communication norms. This research provides insights into how presidential communication has evolved and how linguistic patterns reflect broader societal and political changes throughout American history.