John Lewis Martin was born in Eagle Lake, Maine. At the age of three, his parents moved from Eagle Lake to Brownville Junction; he grew up speaking French and English. Martin was graduated from Fort Kent Community School in 1959 and afterwards spent two years at the University of Maine, Fort Kent before transferring to the University of Maine, Orono, graduating in 1963. While doing graduate work, he was elected to the Maine state legislature as a Democrat in 1964. He served in the Maine House of Representatives from 1964-1994 and was speaker of the house from 1975-1994. During that period, he also held a number of other positions, including teaching at various colleges and high schools in northern Maine and serving as a campaign aide to Senators Edmund S. Muskie and George J. Mitchell.