It is hard to believe these are photos of the same dress, but compare the details of the embroidery, piping, and the ribbons trailing behind. The left image is from From historicalfashion.tumblr.com/tagged/russian+imperial+court/page/2. The right image is from costumedramas.tumblr.com/page/10.
The left image came with this note, "Unfortunately this is only the side of it, but look at the detail! Fabulous!
A Russian Imperial Court dress from the late Regency period of the 1820s. It is made of a blue silk moire, or watered silk, fabric. In reference to other Russian Court dresses, this one is moderately simple. It is interesting to see how the Court dress stayed true yet changed with the fashions at the same time.
Notice how the layers of fabric and decoration at the hems and how they are weighted with what looks like piping (with a very large cord). This was all done by HAND!"
The right hand image links back to historicalfashion.tumblr.com/post/16199743160/russian-court-gown-1820s-one-of-the-things-that. The right hand image came with this note, "One of the things that fascinates me most about Russian court gowns is that they still retain elements of the current fashions, like the waistline of the late 1820s here, while having all the requirements of court fashion."
The back of the bodice has a triangular panel that appears to come to a point beneath the bow where two much larger ribbons trail almost to the edge of the train where they are tied off and decorated with small pom poms.