[ansel12]

They were somewhat common by the late 1600s, although the population groups here were still tiny and pretty homogeneous.

[cripplecreek]

From wiki for further investigation.

In the United States, until the mid-19th century, common-law marriages were recognized as valid, but thereafter some states began to invalidate common-law marriages. Common-law marriages, if recognized, are valid, notwithstanding the absence of a marriage license. The requirement for a marriage license was used as a mechanism to prohibit whites from marrying blacks, mulattos, Japanese, Chinese, Native Americans, Mongolians, Malays or Filipinos. By the 1920s, 38 states used the mechanism.