What does out of many mean?

Answer 1

When the founding fathers chose the Latin phrase E Pluribus Unum - out of many, one - as the national motto, an event that took place concurrent with the 13 colonies declaring their independence, the intent was to dramatize the reality that these 13 separate entities had indeed come together as one. Over time, the motto, which cannot be found in any classical Latin text, has been used to describe the America that evolved from the immigrant experience.