Create a timeline that displays the relationships between a specific subject and their associates, based on information about that subject obtained from multiple documents. [Solution] The information acquisition means acquires subject-related information related to a specific subject from multiple documents. The extraction means extracts multiple strings that meet predetermined criteria from the subject-related information. The analysis means organizes the multiple strings according to a predetermined format for the specific subject and for people other than the specific subject, and detects strings that have a predetermined relationship among the multiple strings, and outputs the organized strings and information indicating the relationship. The timeline creation means creates a timeline that displays strings related to the specific subject and strings related to people other than the specific subject in parallel on a timeline, and also displays information indicating the strings that have a relationship among the multiple strings.