Initiative is defined as a hierarchy- epics & stories roll up into it. A Theme also sounds similar as a business objective that multiple epics/stories map into. When is a Theme recommended to be used versus an Initiative.
Themes can be used to categorize work across the organization, while initiatives are collection of Epics
For example: In Car manufacturing company, themes can be Manufacturing, Designing, QA etc..
Also, we can use these themes to target certain percentage of overall work (Tracked under Reports in Portfolio)
Check this : Epics, Stories, Themes and Initiatives
Hi All! We’re excited to share the launch of an announcement banner that lets Jira site administrators communicate directly to their users across their Jira Cloud instance. ...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events