Here is a quick little tip on dating your vintage clothes!
Care Labels became a requirement for garments in the United States in 1972. So if you've got a vintage dress that looks like it's from the 1950s but there is a Care Label... then you know it's not from the 50s! The Federal Trade Commission (FTC) decided upon the Care Labeling Rule on Dec 16th, 1971, it was later amended in 1983.
Some clothes made earlier than 1972 sometimes included a Care packet or booklet with the dress, but not a SEWN-IN label.
Hope that helps a bit in helping you date or determine the age of your vintage clothes!