Why was 1774 such an important year leading up to the American Revolution?

At the spring of 1774, between May and June, the so-called Intolerable Acts take place: The British Empire imposes four drastic measures to Massachusetts, removing its self-government and its independence in matters of law. This was product of the Boston Tea Party. This act prompted the 13 Colonies to reach an agreement to boycott the products of Great Britain. Then, in September of that same year, the colonial delegates met to plan and organize an opposition against the impositions of the British Empire in the Continental Congress.