Allen G. Thurman completed his early education at Chillicothe Academy and pursued legal studies under his uncle, William Allen. He gained early professional experience as a private secretary to the Governor of Ohio, Robert Lucas, before being admitted to the Ohio bar in 1835. Thurman later became a law partner to his uncle, William Allen, who was a member of the Senate. His foundational background includes a blend of political apprenticeship and legal expertise, establishing a solid base for his subsequent career achievements.

Allen G. Thurman's political identity is marked by a calculated approach to regional industrial interests, as evidenced by his unexpected convergence with opposing factions on environmental regulations. His legislative record suggests a strategic ideological agility, balancing progressive stances with protectionist measures. Thurman's rhetorical style is steeped in historical precedents, using past resolutions to justify contemporary actions, such as citing his own resolution against William W. Belknap to argue for Donald Trump's impeachment. This reliance on historical analogies indicates a deeply rooted, almost antiquarian method of policymaking.