Harald Olafsson: Why is the author so quiet on the climatic year of 1066? He just glosses over events in a very short paragraph?

Although we often refer to 'the' Anglo-Saxon Chronicle, we must always remember that we are in fact talking about several documents. Many of the entries are very similar to, if not exactly the same as, the entries in other versions. But sometimes the versions are either substantially or wholly different, and the entry for 1066 is one of those that differs substantially. Also, even in the same version, the chronicler might have got confused about dates and put another entry about the same year under a different date, for example.

I think that the version you're referring to, Harald, is the 'A' version, which says:

Her forðferde Eaduuard king. Harold eorl feng to ðam rice heold hit xl wucena ænne dæg. Her com Willelm gewann ængla land. Her on ðison geare barn Cristes cyrice.

In this year passed away king Edward, and earl Harold came to the throne and ruled for forty weeks and a day. In this year came William and conquered England; and in this year Christ Church [Canterbury] was burned, and a comet appeared on 18 April.

As for why the entry is as short as it is, I don't know. The other versions are all a lot longer than this, but these are all unusually long entries, so maybe our 'A' chronicler didn't think it necessary to add any more than these very bald facts. The Battle of Fulford site offers a good comparison of the entries for 1066, but I'd get your hands on a proper copy of the Chronicle since it doesn't seem like your one's up to much! The version I've got is by Garmonsway, and the introduction is a good account of the various different versions of the Chronicle. I've seen a newer version that's based on Garmonsway but the name escapes me for the moment. Hope this helps.