In the early years of Pennsylvania, the Penn family invited settlers of all kinds to colonize the state. To this call, responded many Irish, mostly from the northern Irish provinces. The massive Irish emigration was unexpected and they were not the most respected people. But it was too late to retract the open immigration policy.

The Irish settled in the counties of Chester, Lancaster, Northampton and Northumberland. As well, a large population settled along the Maryland line in the area disputed between the Penns and Lord Baltimore. This land was suitable to squatters, which many of the Irish were, because it was not yet for sale and was considered hard to govern, given the land dispute.

Beginning in the early 1700’s German emigration from the Palatinates on the Rhine brought large, strong, community orientated, industrial groups to the same Pennsylvania counties of which the Irish had already immigrated to. These Germans were known for prejudice against the Irish whom they considered not suitable to be colonist. As well, the Quaker proprietors of Pennsylvania considered most of the Irish to be stubborn squatters, as many of them truly were. Quarreling was abundant.

The Irish, bowing to some of this pressure, as well as being generally hardy, stubborn and bold people, gradually began migrating west or south-west. The Irish were known for being intolerant of Indians, as well as against others who had any prejudice against them, and so disputes were many. In the mid 1700’s the disturbances between Germans and Irish encouraged the Pennsylvania proprietors and administrators to convince Germans to migrate to the eastern part of the state and the Irish to migrate westward.

Large parts of York County were settled by these migrating Irish, and later many of the settlements became a part of Adams County which is largely Irish today. A little later they began migrating west along the Juniata River and over the Alleghany mountains. Since this was prior to land settlement agreements reached between the Penn family and the native Indians, this caused more disturbances between the Irish and the Indians.

Eventually one disputed area after another was settled, and treaties made, much of the time just after very violent skirmishes between the Irish and the Indians. It seemed that as soon as an area was officially settled, the Irish would again migrate westward to yet more unsettled territory. When the Pennsylvania counties west of the Allegheny River were official declared and mapped, the Irish had already been there for some time. During this same period, many of the Irish joined military ranks and fought in the Revolutionary War. They were known as tough and ready fighters.

In 1795, owing to a ratified treaty made by General Wayne and the Indians, it became safer to cross the Allegheny River and settle lands there. The bold, ever curious Irish were the first to rush into this area in mass and begin families and farms. It wasn’t long until most of western Pennsylvania, near the Ohio border, was predominantly Irish and Scotch-Irish. The migration of the Irish across the state was complete.