As there was in the year 2000(CE), is there any evidence that suggests that there were there celebrations commemorating the start of the first millennia in 1000(CE)?

You may be interested in "Did people in 999 AD celebrate the new millennium? Were there any doomsday predictions similar to Y2K?" , reply by /u/haimoofauxerre . But note that that's about fears of Armageddon, rather than about celebration.

So this is a starting point, not to discourage discussion. I hope we see more discussion, data, and debate.