Query case history and field change events for Salesforce Service Cloud cases via SOQL

In-depth guide

Steps

1. Authenticate to the Salesforce REST or SOAP API with an OAuth access token; ensure the connected app or user has Read access to the CaseHistory object.
2. Query the CaseHistory object to retrieve field changes for a specific case: SELECT Field, OldValue, NewValue, CreatedDate, CreatedById FROM CaseHistory WHERE CaseId = 'your_case_id' ORDER BY CreatedDate ASC.
3. To retrieve history across many cases efficiently, add a CreatedDate range filter: WHERE CreatedDate >= LAST_N_DAYS:30 and paginate using the nextRecordsUrl in the REST API response.
4. For fields tracked beyond the standard 18-month CaseHistory retention window, query the FieldHistoryArchive object (requires Field Audit Trail add-on): SELECT ParentId, Field, OldValue, NewValue, CreatedDate FROM FieldHistoryArchive WHERE ParentObjectType = 'Case' AND CreatedDate >= {date_literal}.
5. Map the Field column values (which are internal API names) to user-friendly labels using the case object's field metadata endpoint or a static lookup table.
6. For compliance exports, combine CaseHistory with SetupAuditTrail (for admin-level configuration changes) and CaseComment, CaseFeed for a complete case activity picture.