Once upon a time people lived off the land. They were in small towns or living out on farms or villages. There was not always a priest around so … couples would declare their love for each other in front of whoever was around. The witnesses were probably family and neighbors. They used a cord or scarves to tie their hands together.
Since you can’t tie your hands yourself they had to incorporate help. The person they asked to do it might have been a shaman type ? Often people would and still do worship nature.
In doing this as a public declaration we know … that they knew what they were doing. In those times marriage was a lifetime commitment. You just didn’t get out of it like today. It wasn’t socially acceptable to be married several times unless you were a widow. By inviting guests you are making your love statement so the whole community knew you were hitched for life. And it's no fun to do this by yourselves. It's much more fun to have others to celebrate with.
Today we build upon the tradition with a non-religious version. No hailing of the Mother Nature as god. I would never call myself a goddess and would never want to freak your family out. This ceremony is a beautiful visual representation of the vows as promises and the physical cords or ribbons as binding.
I’ve been to a Cemetery in Iowa and have seen the title “Consort” on a family head stone. Apparently this means that an Aunt never had a proper marriage. The family record says that the Holy Man never got around to those parts. I wonder what their public declaration was like ?