Henry B. Cleaves completed his early education in local schools and Bridgton Academy. He served in the American Civil War, rising from Private to Lieutenant. After the war, he managed a family farm and engaged in the lumber business. Cleaves pursued a legal career, studying law and establishing a successful practice in Portland, Maine. He held various political positions, including serving in the Maine House of Representatives, chairing the House Judiciary Committee, and acting as city solicitor for Portland. He later served as Maine Attorney General and Governor of Maine, addressing significant economic challenges during his tenure.

Henry B. Cleaves exhibits a unique blend of legal acumen and regional advocacy, leveraging his experience in law and public service to navigate economic crises. His legislative tenure reveals a calculated approach to regional industrial interests, particularly during the national economic depression of 1893. Cleaves's political career, marked by his rise from a private soldier to Governor of Maine, suggests a strategic ideological agility that balances local economic needs with broader national challenges.