These are the most popular given names in the United States for all years of the 1920s.
1920
Males John William James Robert Joseph Charles George Edward Thomas Frank Females Mary Dorothy Helen Margaret Ruth Virginia Elizabeth Anna Mildred Betty
1921
Males John Robert James William George Charles Joseph Edward Frank Thomas Females Mary Dorothy Helen Margaret Ruth Mildred Betty Virginia Elizabeth Anna
1922 Males John Robert James William Joseph Charles George Edward Richard Frank Females Mary Dorothy Helen Margaret Ruth Betty Frances Elizabeth Virginia Anna
1923
Males John Robert William James Charles George Joseph Edward Frank Richard Females Mary Dorothy Helen Margaret Betty Ruth Mildred Virginia Frances Elizabeth
1924
Males John Robert James William Charles Joseph George Edward Richard Donald Females Mary Dorothy Helen Betty Margaret Ruth Virginia Frances Doris Mildred
1925
Males John Robert James William Charles Joseph George Richard Edward Donald Females Mary Dorothy Betty Helen Margaret Ruth Doris Virginia Elizabeth Evelyn; Mildred (tie)
1926
Males Robert John William James Charles George Richard Joseph Edward Donald Females Mary Dorothy Helen Betty Margaret Ruth Virginia Doris Jean Maria
1927
Males Robert James John William Charles Richard George Joseph Donald Edward Females Mary Betty Dorothy Helen Margaret Ruth Virginia Doris Maria Shirley
1928
Males Robert John James William Charles Richard Donald George Joseph Edward Females Mary Betty Dorothy Helen Margaret Ruth Barbara Doris Maria Patricia
1929
Males Robert John James William Charles Donald Richard George Joseph Edward Females Mary Betty Dorothy Helen Margaret Ruth Doris Maria Barbara Shirley
See also Popularity of birth names for females (United States)
References Most Popular 1000 Names of the 1920s from the Social Security Administration