"Most" vs. "most of"

Solution 1:

The sense of history used here identifies a particular period. Now just what that period is may be unclear or may differ between similar uses (in particular, whether prehistory—the period before writing was invented and hence written records available—is included or not will differ between uses).

But despite this ambiguity, it still refers to one particular thing. While we do not capitalise it, it's more a proper noun in this sense than it is a common noun, for just as Jon identifies one person (in a given use), history in this use identifies one period, albeit the period that covers everything.

Other uses of history are countable or mass uses:

To take StoneyB's examples:

Most history is lies.

This uses history as a mass noun to cover all that is said about the past. Hence most is used to identify the greater part of that mass, that is to say the greater part all that is said about the past.

Most histories are boring.

This uses history as a countable noun, to refer to a particular account. (Or rather in the plural, to refer to particular accounts). Here most identifies a certain number of this plural amount.

During most of history, humans were too busy to think about thought.

This uses history as a proper noun, to refer to a particular period in time. We could interpret it either as since writing began, or since humans began (from context we clearly don't care about earlier than that), but however we interpret it, it's talking about one individual, particular period.

It uses most of to identify the larger part of that particular period.

In comparison, water:

Most waters are healthy.

Uses water as a countable noun, in the plural (as can be done to differentiate water from different sources), and applies most to that plural number.

Most water is healthy.

Uses water as a mass noun, and applies most to that mass.

Now, we don't have a sense of water on its own that applies to one individual. We can though use "the water" to apply to a particular bit of water.

Most of the water is healthy.

Again, because we're dealing with an individual case, we use most of rather than most

Generally we use "most…" or "most of the…". The first refers to the majority of all that the noun phrase refers to "most butterflies are pretty". The second refers to a particular identified set of what the noun phrase refers to "most of the butterflies I've seen were pretty".

The difference is unspecific group vs. specific group.

Because history in the sense of the question is already specific, without a definite article, we're essentially using the "most of the…" form, but without the the.

Likewise, with proper nouns, we only use the if the is normally part of that proper noun; "Most of Europe" and "Most of the Rolling Stones" differ because we don't say "the Europe" but we do say "the Rolling Stones".