1891, Washington state law required county governments to begin recording birth and death records. At the same time, most counties also began a corresponding effort to collect additional information on marriages. King County did this by collecting additional statistical and personal information on marriages beyond what was required by law. The instrument utilized was the marriage return
he return form was filled out by the ceremony officiator and filed with the County Auditor after the marriage ceremony. It included detailed personal and statistical information on the couple and on the ceremony itself. The bulk of the records comprise the years 1891 to 1915 and correspond to most marriages for those years. Few returns are present between 1916 and 1947 and account for less than 1% of marriages for each year.
as part of the task of keeping marriage returns, Washington counties also kept corresponding registers of marriages. The King County marriage registers also serve as indexes to and transcriptions of the original forms (b. Register of Marriage Returns).