First of all I assume you are talking about the year 1000 of the calendar most of the world uses today? The answer lies in the fact that I have to make the assumption in the first place.

There have been many different calendars throughout history, the Anno Domini (AD) one we use right now was thought up in 525 AD, and has gradually spread throughout the world, some parts of the world adopting it only in the 20th century as their official calendar.

So, most people would have been unaware of the year 1000, simply because they used a different calendar. Most people in Western Europe still used regnal years (X amount of years since the start of the reign of the current Sovereign) in the year 1000.

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No, it wasn't, largely because many weren't aware that it was 1000 years since the birth of Christ. Ironically, this was a much feared event (referring to the apocalypse), but during the tenth century there was a radical change in the theories about the apocalypse so people no langer had any reason to anticipate this event.