Final answer:
The essays that were widely published across pre-Revolutionary War America and criticized the British political system were known as Cato's Letters. Authored by John Trenchard and Thomas Gordon, they deeply influenced American political thought and contributed to the ideological foundation of the American Revolution.
Step-by-step explanation:
The essays that criticized the British political system and were cited as a source of revolutionary ideas nearly 50 years later are Cato's Letters.
Cato's Letters were a series of essays published in British newspapers in the 1720s by John Trenchard and Thomas Gordon under the pseudonym of Cato. These essays deplored corruption in the British political system and spoke to the defense of liberty, the rule of law, and freedom of speech. The critiques and ideas discussed in Cato's Letters powerfully influenced American political thinking. Even decades later, these essays were republished in the American colonies and served to fuel dissatisfaction with British rule, laying an ideological groundwork for the American Revolution.
The American colonists were forming their own institutions such as the Continental Congress, influenced by political ideas from the British radicals. The revolution was sparked by a combination of Enlightenment ideas regarding popular sovereignty and natural rights, the colonists' desire for economic freedoms and self-governance, and the political thought of influential philosophers like John Locke. These multifaceted reasons combined with growing popular protest, ultimately leading to the outbreak of the Revolutionary War.