The ancestral background of presidents of the United States has been relatively consistent throughout American history. With the exception of Martin Van Buren and perhaps Dwight D. Eisenhower, every president has ancestors from the British Isles, which in turn makes many of them distantly related to one another. John F. Kennedy was of pure Irish descent, Van Buren was of Dutch lineage; and Eisenhower was of German and Swiss heritage. Barack Obama is the only president to have ancestry from outside Western Europe; his paternal family is of the Luo people of East Africa. He is also believed to be a direct descendant of John Punch, a colonial-era slave born in modern-day Cameroon. Despite speculation, there is no evidence that any of the United States’ presidents have had any Indigenous American ancestry.
 The most common ethnic groups in the Thirteen Colonies were those hailing from either Great Britain or Ulster which includes 9 counties of Ireland, 6 of which are in modern day Northern Ireland. Those of other backgrounds (such as Irish, Dutch, German, or French) would see attempts to assimilate them into the dominant English and predominately Protestant culture.
 Some nativist political groups within the United States were adamantly opposed to identifying with a foreign nation and would coin those who did as hyphenated Americans. Presidents Theodore Roosevelt and Woodrow Wilson were outspoken opponents of hyphenated Americans, with Wilson once remarking, "Any man who carries a hyphen about with him, carries a dagger that he is ready to plunge into the vitals of this Republic when he gets ready."
 Summary: Dutch – 5 •  English – 39 •  French – 12 •  German – 11 •  Irish – 4 •  Kenyan (Luo) – 1 •  Scottish – 19 •  Swiss – 3 •  Ulster Scots – 21 •  Welsh – 15
 {{Debate: the distinction between Irish and Ulster Scots separate ethno-nationalist groups is a post-Great Irish Famine invention used by Irish-American Protestants to differentiate themselves from Irish Catholics at a time when Irish Catholic immigrants were widely discriminated against in the labour market, housing, and other areas. Prior to the 1840s, the early US presidents  listed on this page as  Ulster-Scots would not have described themselves as such And would likely in fact have considered themselves Irish and/or British. This table should not therefore identify the two as separate categories.}}
 Augustine Washington
 Mary Ball
 John Adams Sr.
 Susanna Boylston
 Peter Jefferson
 Jane Randolph
 James Madison Sr.
 Nelly Conway
 Spence Monroe
 Elizabeth Jones
 John Adams
 Abigail Smith
 Andrew Jackson Sr.
 Elizabeth Hutchinson
 Abraham Van Buren
 Maria Hoes
 Benjamin Harrison V
 Elizabeth Bassett
 John Tyler Sr.
 Mary Armisted
 Samuel Polk
 Jane Knox
 Richard Taylor
 Sarah Dabney Strother
 Nathaniel Fillmore
 Phoebe Millard
 Benjamin Pierce
 Anna Kendrick
 James Buchanan Sr.
 Elizabeth Speer
 Thomas Lincoln
 Nancy Hanks
 Jacob Johnson
 Mary McDonough
 Jesse Root Grant
 Hannah Simpson
 Rutherford Hayes Jr.
 Sophia Birchard
 Abram Garfield
 Eliza Garfield
 William Arthur
 Malvina Stone
 Richard Falley Cleveland
 Ann Neal
 John Scott Harrison
 Elizabeth Ramsey Irwin
 William McKinley Sr.
 Nancy Allison
 Theodore Roosevelt Sr.
 Martha Bulloch
 Alphonso Taft
 Louise Torrey
 Joseph Ruggles Wilson
 Jessie Janet Woodrow
 George Tryon Harding
 Phoebe Elizabeth Dickerson
 John Calvin Coolidge Sr.
 Victoria Josephine Moor
 Jesse Hoover
 Hulda Randall Minthorn
 James Roosevelt I
 Sara Ann Delano
 John Anderson Truman
 Martha Ellen Young
 David Jacob Eisenhower
 Ida Stover
 Joseph P. Kennedy Sr.
 Rose Fitzgerald
 Samuel Ealy Johnson Jr.
 Rebekah Baines
 Francis A. Nixon
 Hannah Milhous
 Leslie Lynch King Sr.
 Dorothy Ayer Gardner
 James Earl Carter Sr.
 Lillian Gordy
 Jack Reagan
 Nelle Wilson
 Prescott Bush
 Dorothy Walker
 William Jefferson Blythe Jr.
 Virginia Cassidy
 George H. W. Bush
 Barbara Pierce
 Barack Obama Sr.
 Ann Dunham
 Fred Trump
 Mary Anne MacLeod
 Joseph R. Biden Sr.
 Catherine Eugenia Finnegan