As recently as 1960, Aroostook County had more people than York County. In 1860, Washington County had a larger population than most of the midcoast.
Changes during the past 155 years give a shorthand look at Maine’s economic and political history, with southern and central Maine counties gaining in Maine’s population rankings.
Below, each county is represented by a line, tracking its rank in each census year and the most recent population estimates, from the 2015 American Community Survey.
The archival county-level information from the U.S. Census Bureau does not have more detail on Maine’s migration patterns or specific reasons why people moved, but general economic history tells at least part of the story.
The rise of railroads and starch factories in Aroostook County in the 1870s led to a boom in the region that lasted through the 1960s, when the federal government closed the Presque Isle Air Force Base.
Washington County through the early 1900s had a fairly flat population, lowering its ranking against areas of the state and leaving it the only county in the state to have fewer people in 2015 than in 1860, when sardine canneries were a major economic engine.
It had steady population declines through the early 1900s until 1980, when urchin harvesting and farmed salmon operations cropped up.
In more recent history, southern Maine’s top two biggest counties have outpaced growth farther north, with York County overtaking Penobscot in the 1980s and keeping a 50,000-person lead through 2015. Cumberland County has held the top spot for the entire period.
Below, see those population trends in absolute numbers, color-coded by decades in which there were increases or decreases from the previous census.
Maine’s population will continue to be an issue for the state’s economy and workforce in years ahead. In looking back, let me know what you see as the most important trends that to influence the future of the state’s economy.