I'd say 1950s, and I wouldn't wash it. It looks top be either a rayon or silk faille, and that won't like getting wet. You could have dye run or shrinkage. And those covered baubles may not do very well. This is a fabric that also gets tide rings from moisture, so that means no spot cleaning. If yo have a good dry-cleaner, that may be the way to go.
Let's see what the others say. They may have some ideas on cleaning.