My calendar events disappear after a couple of months

Go to Settings/Calendar/accounts. Tap on the account (unless it is iCloud) and log for a setting “Mail days to sync”. Note that not all account types support this, and iCloud does not because it syncs all events forever.

Also, the built in calendar app can only search the previous 12 months, even though you can view older events. There are several 3rd party calendar apps in the app store that can search any date range; I can search back to 1998 because I imported my Palm Treo calendars when I first got an iPhone.

This is helpful reply. But it highlights a foolish limitation imposed by Apple. They could give us an option of time frame for a search but choose to simply make iCloud calendar a poor way to record calendar-related information.

Apple’s calendar is very basic. There are several 3rd party calendar apps that are much more powerful, and let you specify a search range. Many built in apps are basic, possibly to developers don’t feel Apple is trying to compete with them. I use WeekCal, another popular one is Fantastical. Both have some amazing features, such as event templates, group templates to insert a bunch of related events, and much more.