There is a default preference to not sync calendar entries older than 3 months. You can change it and get them back.
What you said
Also, if your using iCal it has a preference setting for when to delete past events. Look in Preferences /advanced
I don't see that option readily available, either on the iPhone or on iTunes.
We are on a PC, therefore not using iCal. Where exactly is that option, or do I need to turn on synching before that option is available?
( . . . as you might guess, I'm being told what to ask by my husband. I don't understand ANY of this stuff!!!)