Other forms: prosopographies
A prosopography is a collective study of a specific group of people. It's like a "collective biography" focusing on common traits or connections throughout the lives of a group, such as the rock stars of the 1970s.
Prosopography originally meant the study of a person's physical appearance. But today, the word is almost exclusively used by historians to describe the study of the common characteristics among an entire class of people — e.g., the influential women who fought for a woman's right to vote in the 18th and 19th centuries. As opposed to biographies and autobiographies, which focus on one main person, prosopographies use the stories of many individual lives to tell a larger story about society.