Constance Cummings was born Constance Halverstadt in Seattle, Washington on May 15, 1910.
The best thing I've read about Cummings is the entry in William M. Drew's At the Center of the Frame, which I'll give you a little more information about below. The Constance Cummings chapter, like the others in the book, opens with a fine biography of the actress by Drew, before handing over the bulk of the text to Cummings herself. In this case the author spoke with the star in April 1992.
A brief excerpt finds Cummings recollecting the simplicity of her life during the early Hollywood phase of her career:
During my years in Hollywood, I lived very quietly. I never got up to any pranks and I never did any publicity stunts that would have invited attention. Some people did, you know. They would do anything to get a bit of publicity. But my mother and I lived quite simply in a very nice little house on Sunset Boulevard. We didn't live in the Hollywood style with great entertaining or anything like that. We didn't even have a maid or a cook—it was just me and my mother. I drove a little Ford car—I remember it distinctly. It was the first car I'd ever owned and I was very pleased with it because it was my first.
Drew, William M. At the Center of the Frame: Leading Ladies of the Twenties and Thirties. Lanham (MD): Vestal Press, 1999: 244.
The Drew book is highly recommended for its coverage of Cummings and nine other early talkie stars: Billie Dove, Fay Wray, Annabella, Anita Page, Dorothy Lee, Marian Marsh, Evelyn Venable, Jean Muir, and Claire Trevor.
Each chapter is in the same style, beginning with the author's biographical overview and concise recollections of each actresses' career, followed by in depth interviews with each of these stars. I wish I knew of it back when I wrote about Marian Marsh and, especially, Jean Muir! Since it's a slightly older book, published in 1999, it sometimes offers the final word on and from the selected stars. A fascinating book.
It's that first phase of Constance Cummings' career that is of primary interest to this site, and you'll find Miss Cummings featured in reviews of The Criminal Code (1931), Washington Merry-Go-Round (1932), and The Mind Reader (1933).
Constance Cummings lived to age 95. You can revisit her 2005 New York Times obituary here.