Stop Facebook birthdays and events from appearing

Since iOS6, Apple made it possible to link your Facebook account directly to your iPhone. By default, Calendars and Contacts sync is enabled, which will sync your Facebook events and birthdays to your iPhone's calendars and thus to Week Calendar.

How to stop Facebook events / birthdays Sync?

  1. Go to System Settings
  2. Go to Facebook
  3. Toggle Contacts to OFF if you don't want birthday events from Facebook
  4. Toggle Calendars to OFF if you don't want Facebook events

If the events do not disappear:

Open up the native (Apple) iPhone Calendar app once to force your iPhone to remove all facebook synced calendar contents.