Both a Statement of Purpose and a Personal History Statement are required for applicants to the UCI Ph.D. in Education program (limit of 1,200 words each). Though you may include overlapping content in them, the former is much more geared to your research background and trajectory, and the latter emphasizes your personal background.
Here is a brief explanation of what should be included in each.
Statement of Purpose
A Statement of Purpose is required for applicants to the UCI Ph.D. in Education program. In your Statement of Purpose, please describe your career goals, your research interests, how/why you think the UCI Ph.D. in Education program and its faculty can help you to achieve your research and career goals, and what about your background and experience has prepared you to become an outstanding educational researcher.
Personal History Statement
A Personal History Statement is required for all applicants to the UCI Ph.D. in Education. In your Personal History Statement, please discuss how your personal background—including any relevant educational, familial, cultural, economic, or social experiences, challenges, or opportunities—informs your decision to pursue a Ph.D. in Education. You may also discuss, if you wish, how you might contribute to social or cultural diversity within educational research or to the improved education of diverse groups.