How the Potato Changed the World's History

Social Research, Spring, 1999 by William H. Mcneill

The Irish reoccupation of the southern part of the island took place because Protestant English landowners found a work force willing to live on so slender a base irresistible. Accordingly,. Catholic Irish laborers soon seeped back into the provinces from which their ancestors had been forcibly removed, living as impoverished rent payers and wage earners. Then, in the latter decades of the eighteenth century, rising grain prices in England persuaded a good many landowners in the drier parts of the island to plow up pasture land and plant grain. This multiplied wage work; and the Catholic Irish population responded by growing very rapidly indeed. Early marriage prevailed. A couple needed only an acre and a cow to start a family; and landowners soon found themselves renting out more potato land than was needed to support the number of laborers they could usefully employ.

After 1815, grain prices collapsed and Irish landowners tried to go back to grazing. But there was no way for them to clear the land of surplus laborers, who found themselves desperately bidding against one another for the right to plant potatoes on a suitable patch of land. The unhappy result was that a bitterly impoverished and rapidly growing rural population confronted not very prosperous landowners across an inflamed religious barrier.

The Irish question that haunted British politics until our own time thus took form, reaching an especially acute and terrible climax in 1845-47 when the sudden outbreak of blight came near to destroying the entire potato crop. More than a million died of famine, typhus, and other diseases in those two years and by 1850 more than another million had emigrated (mostly to the United States). The Irish Diaspora affected all the lands of European settlement overseas, and continued into the twentieth century as rural Ireland was slowly transformed into a land of small mixed farms where grazing and dairying were more important than any crop--even, or especially, potatoes. In its own small way, therefore, the strange career of the potato in Ireland had worldwide impact, not least on the United States of America.

But what really dominated the global scene between 1750 and 1950 was the extraordinary ascendancy that a few states in northern Europe exercised over all the earth on the strength of industrial, political and military transformations which could not have come about without an enormously expanded food supply from fields of potatoes.

England, where industrial transformation concentrated at first, was unusual since potatoes played only a modest part there. Exceptionally efficient commercial grain farming together with the early start of industrialization allowed bread to remain the staff of life for the English working classes. To be sure, potatoes had begun to supplement bread in northeastern England a few decades before 1700, but they never became the sole support of large numbers of people, as in Ireland. Beginning about 1730, however, the Scottish Highlands went over to potatoes as completely as Ireland had done so that, when I was young, my mother started supper by putting potatoes in the oven before thinking about what else there might be for us to eat. And the Scottish Diaspora that followed hard on the heels of the highlanders' defeat at the battle of Culloden in 1745, was a lesser version of the Irish Diaspora of the following century. It had a similarly widespread impact, though with interestingly divergent social and economic effects both in Scotland and abroad. But that is another story whose investigation would divert me from my proper theme.(3)