Calvin Coolidge (1872-1933), 30th President of the United States (1923-1929) was, through his paternal grandmother Sarah Almeda Brewer (1823-1906), a descendant of John Brewer of Cambridge, Massachusetts (1641) and Sudbury, Massachusetts.
President Coolidge's Brewer ancestors moved from Worcester, Massachusetts to Ludlow, Windsor County, Vermont in the early 1800s. His great-grandfather, Israel Chase Brewer, and some other relations later moved on to Wisconsin. During his time in office, President Coolidge made several trips to Wisconsin and looked up his relations who had established themselves there. Among those Brewers who he encountered were descendants of Jeremiah Brower/Brewer of Highgate, Vermont. As the story was related to me by present day descendants of Jeremiah Brower/Brewer (all of whom use the BREWER surname) their Brewer ancestors and President Coolidge believed that they were cousins based simply on the fact that both families had the surname, BREWER, and both had origins in Vermont. At the time, the Wisconsin Brewers descended from Jeremiah Brower/Brewer were clearly unaware of their own correct ancestry. Their correct ancestry has, since the time of President Coolidge, been discovered using both traditional genealogical research methods and DNA testing and comparison of descendants.
In here is the lesson that having a common surname, and a common place of origin (especially one as general as a State), does not ensure a relationship between two parties who share that common name and place in their ancestries.
An ahnentafel of President Calvin Coolidge's Brewer ancestry has been made available online. Additional details and sources for his ancestors can be found at the Brewer Families of New England website. Details regarding Jeremiah Brower (1738-1822) and his descendants can be found at the Brouwer Genealogy Database website.