Её отсутствие удивляло всех.

Here её means her.

It is the genitive form of the pronoun она (she), and it is used because отсутствие often takes the genitive to show whose absence it is:

• её отсутствие = her absence
• его отсутствие = his absence
• их отсутствие = their absence

So она отсутствие would be wrong here.

Отсутствие is a neuter noun. In the past tense, Russian verbs agree with the subject in gender and number.

The subject here is отсутствие, so the verb must also be neuter:

• masculine subject → удивлял
• feminine subject → удивляла
• neuter subject → удивляло
• plural subject → удивляли

So:

• Её отсутствие удивляло всех.

uses удивляло because отсутствие is neuter singular.

Всех is accusative here.

The verb удивлять / удивить takes a direct object: it surprises someone. That means the noun or pronoun for the person affected goes in the accusative.

With все (everyone / all people), the accusative form for animate people looks the same as the genitive:

• nominative: все
• accusative animate: всех

So in this sentence:

• удивляло всех = was surprising everyone

This is one of those very common Russian patterns where the accusative of animate words matches the genitive form.

Удивляло is the past tense of the imperfective verb удивлять.
Удивило would be the perfective past of удивить.

The difference is roughly:

• удивляло = was surprising, used to surprise, or surprised in a more ongoing/background sense
• удивило = surprised as a single completed event

So:

• Её отсутствие удивляло всех.
  suggests her absence was a continuing fact and people found it surprising.

Compare:

• Её отсутствие удивило всех.
  sounds more like one event or one reaction: her absence surprised everyone.

Both can be possible, but they emphasize different things.

Отсутствие means absence.

It comes from отсутствовать = to be absent.

It is a fairly common formal-neutral noun. You will often see it in phrases like:

• в отсутствие директора = in the director’s absence
• отсутствие интереса = lack of interest
• отсутствие доказательств = lack of evidence
• по причине отсутствия = because of absence / due to the absence of

So in your sentence, it literally means her absence.

The subject is отсутствие.

More specifically, the whole noun phrase её отсутствие functions as the subject, but the head noun is отсутствие.

That is why the verb agrees with отсутствие, not with её.

A useful way to see it:

• What was surprising everyone?
• Her absence.

So her absence is the subject.

Yes. Russian word order is flexible, and changing it changes emphasis more than basic meaning.

Neutral order:

• Её отсутствие удивляло всех.

Other possible orders:

• Всех удивляло её отсутствие.
  Emphasis on everyone
• Удивляло всех её отсутствие.
  More literary or dramatic
• Отсутствие её удивляло всех.
  Grammatically possible, but much less natural here than её отсутствие

For a learner, её отсутствие удивляло всех is the safest neutral version.

You could express a related idea in other ways, but the structure would change.

For example:

• Её не было, и это всех удивляло.
  She wasn’t there, and that surprised everyone.
• То, что её не было, удивляло всех.
  The fact that she wasn’t there surprised everyone.

The original sentence uses a noun phrase:

• её отсутствие = her absence

This makes the sentence more compact and slightly more formal or written in style.

In normal modern writing, её is written with ё, and it is pronounced roughly ye-YO.

So:

• её отсутствие

sounds like yi-YO ot-SOOT-stvi-ye (approximate English-style guide).

You may also see ее written instead of её, because Russian texts often omit the dots over ё. But the intended word is still usually её, not a different grammar form.

So in practice:

• её and ее often represent the same word in print
• pronunciation is normally the one with ё

Russian has no articles like a or the.

So:

• её отсутствие can mean her absence
• whether English uses the depends on context: her absence, the fact that she was absent, etc.

Russian usually expresses definiteness through context, word order, and meaning rather than articles.

Also, there is no separate word needed for her own here. Just её отсутствие already means her absence.

Yes, depending on context.

By itself, всех literally means everyone or all of them in the accusative/genitive form. In this sentence, English will often translate it as:

• everyone
• everybody
• all of them

The exact choice depends on context:

• If the group is general or not previously specified, everyone is natural.
• If a specific group has already been mentioned, all of them may fit better.

It is mostly neutral to slightly formal because of the noun отсутствие.

It sounds very natural in written Russian and perfectly normal in speech too, though in casual conversation people might also say something more direct, such as:

• То, что её не было, удивляло всех.

So the original sentence is not unusually literary, but it is a bit more compact and abstract than everyday spoken phrasing.

You can use that to understand the structure, but it is not the most natural English translation in many contexts.

Word-for-word structure:

• Её = her
• отсутствие = absence
• удивляло = was surprising / surprised
• всех = everyone

Natural English usually prefers:

• Her absence surprised everyone.
• Everyone was surprised by her absence.

If you want to preserve the imperfective sense more clearly, you might also say:

• Her absence was surprising everyone.
• Her absence kept surprising everyone.

But in many ordinary contexts, English just uses surprised.