Delaware was first settled by the Swedes in 1638. The area was conquered by the Dutch in 1655 and then by the English in 1664. From 1682 to 1776 the “three lower counties on the Delaware” River were part of the colony of Pennsylvania.
The Delaware River brought the original European settlers to Delaware. For more than three centuries it served as a waterway connecting many Delaware towns to each other and to Philadelphia.
A frequently used land migration route was from Philadelphia to Wilmington and then on to Baltimore. There was very little migration from New York and New Jersey to Delaware, but many people migrated back and forth among Virginia, Delaware, Pennsylvania, and Maryland.
Records
The United States Research Outline (30972) “Emigration and Immigration” section lists several important sources for finding information about immigrants. These nationwide sources include many references to people who settled in Delaware. The Tracing Immigrant Origins Research Outline (34111) introduces the principles, search strategies, and additional record types you can use to identify an immigrant ancestor's original hometown.
In addition, you may find an early immigrant ancestor to Delaware in:
Johnson, Amandus. The Swedish Settlements on the Delaware, 1638-1664. 2 vols. 1911. Reprint. Baltimore: Genealogical Publishing, 1969. (FHL book 974 H2j; computer number 266705; film 1364768 items 8-9; computer number 532940.) General history with index.
Few passenger arrival lists
of Delaware ports exist. The Family History Library and the National Archives have passenger lists on microfilm for the port of Wilmington for the years 1820, 1830-31, 1833, and 1840-49.
The Wilmington passenger arrival lists are included in:
United States. Bureau of Customs. Copies of Lists of Passengers Arriving at Miscellaneous Ports on the Atlantic and Gulf Coasts . . .