How did Speak, Memory change between its first publication and the revised 1967 edition?

The 1967 edition of Speak, Memory, titled Speak, Memory: An Autobiography Revisited, represented a significant expansion and refinement of the original work, which was first published in 1951 as Conclusive Evidence: A Memoir (also released as Speak, Memory: A Memoir).1

The revisions and changes included the following:

• Expansion: The 1967 version was revised and expanded from the original text.1
• Collaborative Input: The updated edition incorporated specific recollections and revisions provided by Nabokov’s sisters and cousins, adding depth to his account of his early life.1
• Visual Additions: The revised edition included the addition of family photographs, which were not part of the initial publication.1
• Contextual Evolution: The work evolved through several stages, including a 1954 Russian translation and revision titled Drugiye berega ("Other Shores"), before reaching what Nabokov considered the "present, final version" in 1967.12

This memoir remains a primary source for understanding Nabokov's aristocratic upbringing in St. Petersburg and his subsequent life as an intellectual and writer in exile.1